Report of Activities - CERN Document Server

Report of Activities in the Divisions

LIBRARIES, GENEVA

LT

Annual Report 1995 — Volume II

EUROP EAN LABORATORY FOR PARTICLE PHYSICS

ISSN 0304-2901

The CERN Annual Report is produced in three Volumes.

Volume 1 is an illustrated, non-technical account of highlights of the year; English and French editions.

Volume 2, the ‘Report of Activities in the Divisions’, is

a detailed, technical account of the year’s work; English edition only.

Volume 3, the ‘List of CERN Publications’, is a catalogue of all

known publications resulting from research done at CERN during the year; single language edition.

The Volumes are produced in limited quantities.

Copies are available from:

Communication & Public Education Group CERN

1211 Geneva 23 Switzerland

5 NT

Report of Activities in the Divisions

Annual Report 1995 — Volume II

EUROPEAN LABORATORY FOR PARTICLE PHYSICS

Contents

Theoretical Physics Division ...... sv eecceeeeeeeeeeeeerernnn nee 1

Particle Physics Experiments Division ...... soccer reeeeereneene

The LEP Programme ..........-..-:.2eccneeeeeeeneenerenneenererneeeeenereereeenenne 3

The LHC Programme ..........:.2222seeeeeeeeeeeeeree esse esneeeeeeerernerererrenene 19

The SPS Fixed-Target Programme ............:-2c22eeeeeeeereneeeeneeeeereneeenernnene 24

LEAR Programme ..........:2222seeeeeeereeeeeeeseeneenneeeeereeeeeeeereneeerere nn 44

ISOLDE Programme ............:.222c2eeeeseeeeeerereeeneenerereeeeneeneneeen nennen 55

R&D Projects ...........-22222eeeeeeeneeeneneneserereneneertereeeeeneereeeenerne nenne 64

Technical Developments ...........:.2222neeeeseeeernersereerenerereeeeereenrerernnne 93

Electronics & Computing for Physics Division ......c.2c00rreer0.. 99

ECP Division . ... 2 oc een ereere ee rereerereesrerereenereeteteeeennes 99

Electronics Unit ... 2 oc co onen eeeeereeeereerereeeteeereeertneene 99

Computing Unit ........222ceeeeeeeneneeneeesnseererenertereneneeeesnrennene ern 108

Computing & Networks Division ........c0ecereeeeereeeeeennenee 117

SUMMAry ..2Ccoeeeeeeeeeneeereeneees sense nneneeseeenerereeeeeeteereseeeeereetenne 117

Distributed Services ....... 2222222 eeeeeeesneneeeseenereeeer een e rennen 118

Physics Data Processing ..........2222222ceeseseeeneeneeneenneneneerereneeeeneeenenne 121

Computing for Engineering ...........2222ceeeeeeereseneeeeeeeeeererneereeeeteenereene 123

Central Database Support .........222ceseeeeeeeeeeeree ner ener nern essen nee eennene 125

Application Software ......22c2seeeeeeeseeeeeeeeeeeeeeeneneeneereeereeneenen nennen 126

Operations .......22e20eeeeeeeeeeeerneneeeneneneneenereerereeeeeeerereeneeeeeenesenne 127

Networking ..........-22222eseeneereneeeneenereereeeren esse eneeneereererereene 128

1995 CERN School of Computing ........: 22222 eeeeeeeeeeneeneeeerseen rennen ernennen 129

Technology ........2.2-222eeeeeeeereereeeeeeereeneeeree nee essen ereresnnen 129

Contents

Accelerator Technology Division .......2e2eeoeneeneserereennne 133 Üryogenics .. 2.2222 2eeeereeeneeeeeneneene nee nenne nenne ernten trete eteeterteeeenn 133

1\) E32 7 PR 135

R7Z. 161111 re 137

Cooling and Ventilation .........2c22ceeeeeseeeensunneuneeneen ernten e ee eee een eeneenn 139

NS] 11 277) Ve 139

Industrial Controls .......... 222-2 esseeseeesneeeeeennenneennneene en eeeeer er enn 140

Optics, Lasers, and Related Developments ......... 222 2esceeeeneeenne nn ene een een en 140

Database Suppott ...........-22ereeeseneesneenneeneeeenenneeteeeeneee rennt eeee nenn 140

Energy Technologies .............c22ceeeeeeeeseeeeeeeneneeneeeree nern ent eeeeeen . 141

Mechanical Technologies Division ......»o.eeeeeeeerereerennenn. 143

General .......2C22eeeeeeeeeeeneeeseeeeeeneneenereerereereesereereeneeererereeeeenn 143

Engineering Suppott ........C2ceseeeeeeenenesneesereeneneenereereereeeeenenereereenn 143

Manufacturing Facilities Group... ..... 222222222 seeseeneeneeeeneenernererenneee nennen 146

Surfaces And Materials Group .........2222seeeseeeeneeeeeeeeneeeeeeeeeneener rennen 148

Installation Support Group .........22ceeeesesneeneneeeeeeeeneneeeenere een terre een 150

Informatics Support ..........2ceneeeeeesenseeneneneneeteeseeeneeenererenereenenen een 150

Proton Synchrotron Division ......ceeeeeeeeessereseneeeeneenne 151

Operation of the PS Complex, and Accelerator Statistics ...... 2222222222 eeeneeeerenenenen en 151

Leptons .......22oueeeereeeneeneneneeer seen neeereeeeeeseeeereesesetseeeeeteteennn 156

Protons .....22.22oeeeeeeeeeneneenenr een eenenereeeeeeeeenesernereenereeeestereenee 156

ÄAntiprotons ........22eeeeeeeeeeeereeeeeeeeeseeeeeeeeeneneeneeeeesteeeeeeeserereeenn 158

(6) TR 159

Experimental Areas .........22ceeeseeeeeeeeseneneeereeneeeeeenenertereterererereneen 161

Computer Controls .......2222eeeeeeeeesseeneeneeeeenenneeeentenenteneneeneeeereeeen 162

Office Computing .........222eseeseeneeeneeeneeneeneneeterereteteteeeeeeeesteeeenee 163

Beam Diagnostics ........2222eeeeeeeeeeeeeeeeneeeeeeereneenseeeeeteeteeeenerterennn 164

Preparations of the PS Complex forthe LHC ...........c22222eeeeeeeeneeeeersen nenn nenn . 165

CERN Linear Collider Studies ........2222cceeessseeeeeeneneeeeneereen ernennen 167

Laser Ion Source Studies .........22coeeeeeeeeseneeeeeneeeeeneeesereereeneeereeeeenene 169

The Antiproton Decelerator Study ........222eceeeeeeeneeeeneeeenseeeeeneeenenentereeen 169

Collaboration with IHEP ...........2222cseeeeseeseneneeeeneeneeserereereenr ernennen 170

SPS + LEP Division ..........22ereeeeeneeeeeeerensnenenennee 171 Accelerator Physics ........ 222222 eeseeeeneeeeeneeeenneeneeeeeerereneneeeenteerneetnen 171

Beam Instrumentation ........2222oeeeeeeeeeeneeneeeeeneeeneeener nenne ren ee nennen 175

Beam Transfer ......... 22222 eeseeeeeeeeeeeeeeeeneneeseneeeeeeenernererereeereneene 176

[6Xe) 111 0) Ve 179

Experimental Areas ........ 2.2.2220 eeereeeensereee esse nern ee e ernennen rennen nen 181

MainRing .........:2o2eeeeeeeeseseseesenereneeeeeeeeeneereeee nee entre tee rennen 183

Operations .......2e22eeeeeeeeeereeeereenneenreeeeerreeeeenerer rent error seerrneene 185

Power Converters .....2.2222eseeeeeeeeeeneeeeeneereseeen essen er reeer teen ere nenne 190

Radio Frequency ..........222eeeeeeneereeeeeeeeseeeeneeereeenee nenne eeeernterrerene 192

Contents

Technical Support Division .......2csseseeeeseeeeseereeeeeenene 201

Civil Engineering .........:22cceneeeeeseeeseereeeseeenenterereseeeesteetereerteeeeen 202

Cooling and Ventilation, Air-Conditioning and Heating............: 2222 coeneeneeneeneneenenn 206

DI Group ..........22ceceeeeeeeeneessneeeeeeeeeneserernenereneseeereereenerereenne 207

Heavy Handling and Transport, Car and Utility Vehicle Fleet, Maintenance of Hoisting

and Miscellaneous Equipment ......... 2222 eseeeeeeeeeeeneeeereneeeneeenereeneeerenennn 208

Electrical Installations ..........: cc ceeeeeeeeeeenenneneeeene nennen retten een nennen 211

Controls and Communications .........22eeeeeeeeneeereneneeenneeneereeerteeeeeereenenn 212

Finance Division ..... 2 ocecooeoon een sonen rer rennen rennen ne 215

Introduction ........222e2seeeeeeeeeeeeneeener esse reneeneeneeneensenereeeeeereesnne 215

Accounting Services .....222o2eeeeeeeeeeneeneenerenereeneereeneeeseeereeeesneeteeene 215

Implementation of the Budget ............2222eceeeeeeeeneeneeeeeneeereeeee nenne ne nen 216

Cash Position .......222e22seereeeerreenee nennen een een eeerererererer ee eeeeeenene 217

Pension Fund ............2e2eoeeeeeereeeeeer een er e een een rrereeeeeeeeereeereerer nen 217

Visiting Research Teams ............:22ccoeereeeeeeeeneeee ne eee nenne nennen ernennen 217

LHC Collaborations ............2222eeeeeeeeeeeener nee nee ern reneen een erener een re nen 217

Purchasing Service ........:.22eceeeseeenereer ner eeeener een ee een ee nee eneerenn ern 217

Budget and Financial Planning ..............2cosoceeeeeeeeerereeeeeenenr seen ernennen 218

Computing, Statistics, Purchasing and Accounting Databases .............-.-u2ceneeeneeen nen 218

Personnel Division ......2oeeeoeeeeeeeeen seen een ernennen nenn ne 221

Review of the Staff Rules & Regulations ..........:.222cceeeeeeeeeesenererer nennen nen 221

Five-yearly Remuneration Review ........2 22220 serreeeneenereereee nee nee erento 221

Merit-Oriented Advancement Scheme ‘MOAS’ .......... 222220 eeeseeneeeeereee ernennen nn . 221

Staff Recruitment ......... 22222 oeeeseeeeneeeneeeneenerneeereneeneenereneeeree rennen 222

Fellows, Associates, & Students ...... co ccooe een neues eneeeeeneeereerereererterrnren 222

Indefinite Contracts ....... 22222 cseeeseeeeeennenneenneeeeeeeeeeneeseererereetreeeene 223

Departures in 1995 ..... 2.222 cooeeeeereeeneeeee nee een enen ee ren e ernennen ene 223

Training .........oo2ooooeeeeeeeeereereeeer nee ern eeeee rer e rennen rrr en nn 223

Health Insurance .........222cooseseeeeeneeneneneeeeeeneen seen eeeeeeeer rennen nern 224

Informatics Systems ........ 2222 cseesseeeeeeneseeseeerenenteeneeseereeeereneerereeene 224

Modified Swiss Regulations ........222222eseeeereeeeeeeer ernennen reererenen een nenn 224

Technical Inspection & Safety Commission .....-».seeeeseseeeeen. 225

General Safety Group ......:.-222eseeeeeerenereen ee nee ers see nern ner een erens 225

Radiation Protection Group .........:22seseeeeeeeerreenerneneeeeereee en eeeenener een en 226

Medical Service ....... 222220 eeeeneeeeeenneer ee eee een nern er en ee e ernennen 227

Chemistry, Fire and Materials Group ...........2222eseeeeeereeeeereerseer nee nen een nn 228

Contents

Directorate Services Unit .... 22 ccceooeeon see e en r een rennen nn 231

Office ofthe Director-General ..........222222eeeeeeeneeeneneeeeneeneeerereeere rennen 231

Office of the Director of Administration ..........:22ceeseeeeeeeeeereeen nee een ern 233

Legal Service .......2 222 o2eeeeeeeeeeerneeeenr essen en ers nee een erenenerenennene 234

Internal Audit Service ........222cceeeeeeeeeeeeenereeeer nennen ernennen eererererene 234

Strategic Planning Unit .........:.22ccoeeeeeneeeenreee nee eenener nenne ennereereennene 234

Industry & Technology Liaison Office .............--:2eveereessereseeeeneerenneeerennne 235

Communication & Public Education Group ..........222ceeeeeeeeeeeeeeneneenne ner en n nenn 236

CERN Pension Fund ......... 22222222 eeeeereneeseeesneee een e nennen ernennen ern en 238

Administrative Support Division ....oscceeseeeeeseeeeenennnnne 239

Data Base Applications Group ...........2cceeeeeeeeenrenereereeneeneeneeennenereeeene 239

Desktop Computer ..... 2.22 c2eeeeeeeneeeeereeneeneer nennen ereeeereereeereneenes 240

Document Handling............2:22eeceneeeeserener nern nee nee neesereeerereneennne 241

General Services ...... 2.22 22eseeeeeeeeeeenereeen ers eren ernennen essen reeeenenne 242

Logistics Services ... 2.2222 cseeeeeeeeeereneen res esse rereenneeeeeeereereeeenererene 243

Scientific Information Services .......2222eeseeeeeeereeeer seen see reneereenerererernen 244

Systems and User Interfaces ..............c2ecseeeeeeeeeesnennerterereeeeneeeererereno 246

Translation and Minutes Service .....:. 2222 cceeeeeereeeereneree en nennen essen eeeeren 247

Organization and Procedures ............---2e22eceeserseenenenenereneeneeterenenerenenn 248

Technological Developments at CERN in 1995 ....... 2.2220 rcec0n. 249

Accelerator Technology .........:.22e20eeeeeeeeeeneenereneererereesreeeeeerereernenno 249

Computing .......222ceeeeeeeeeeeeereneeereener er senereeereeseeeeeeeseeneeseeenereren 252

Computing & Networking ............222s2seseeeeeeeeereneresteeeseeseeeeeeer nennen ‚252

60) 1 (0) VER . 254

(6) 41[0):25 1 (u E 255

Detector Technology ...........222sceeeeeeeeeeneneneee see reeeeeseeenenerererernnene 255

Detectors .....2 22222 eeeeeeeeneenneeeeeeeereer nern erstere rer r nee rennen ereereeen 256

Electronics for Detectors ........2 222222 eeeeeeneerreeer seen een eeneerrereeeene 257

Health Physics ............2222coeseeeeeeeeeneeeneeeees ers neseesereeenerseeneeneene 261

Instrumentation .....:..222eeeeeseeeeeeeeeeeeneeeen een e nern ernennen eeeererene 261

Superconducting Magnets ..........-:2o2ereeeeeesneeeneesreereneenerererereeenerneene 262

Superconducting RF ............2222eeeeeereeeeeerneeeseeeeeeeeereeneenersereeeneeeo 263

Vacuum „2.2 oooeneeeeeeeeeekeeeeeeeeeeeeeeereerennee een eee nee eeeeeenneeenne 263

Contents

Seminars & Colloquia ....... ces esoseeeeeneeeener een re rennen 265

AC Seminars ......2o22ereeeneneeeeer rennen teens r tere eeneeerereereetereenererrene 265

Astrophysics Seminars ........2222eeeeeeeeeeeeeeneenseeeerereeerenereerertenentenene 265

AT Seminars ......2222eeeeesereeeeeeeeneeeeeeeeeeententereeeteeeenerenereeereeeenn 266

CAS Seminars .....222eereeerereeereeeeeneeeenereeeeetereeeestereertereeeeetenereeen 266

670) 1 CoYe 11 ER 266

Computing Colloquia........:222Coeneereeeeneeneeeeeeneeeenerneeeeereeeerterttereeee 266

Computing Seminars ......2C2eeeeeeeeereeereereree een n tee eeereseeeseenterteneenee 267

Detector Seminars ........22eeeeeeeeeeeeenereneeeneereeeeerereesersereteeteeererenee 267

Isolde Seminars ..........2c2ceeeeeeeneeneeeeeeeeeeeeneeeeeeseeseereeereeeererteneen 268

LHC Technical Seminars ..............2..... nennen ereeenereereeeeeereen 268

Meetings on Particle Physics Phenomenology ..........22222eseeeeeeeeeeeeeeernererernenn 268

Particle Physics Seminars .........222cceesseeeeeseeneereeneeneeeserereeeeereeseererene 270

PPE Seminars .........2222cceeeeeeeseeneeeeneeeseeeseenteernessneenerereressererene 271

PS Seminars .......2:22ceeeeeeeeeeereeeeerenneee een ner eenereereeeereereeenerenene 272

Science & Society Seminar ........2eeeeeeeeeeneeenesenereerenereeneererterteentereeen 272

SEMINAIS .. 2.222 eeeereeereeeeeeeeneeeeneenereeeenereenereetteseesseeereeerseeteeene 272

SL Seminars ......2 22222 eeeeeeseeeneeereeneeee essen eneeeeeerereetereeeteeseeetneene 273

Special Colloquium ...........2222eeseeeeereenereenee een ren en erereresereeneeenee 273

Special Computing Colloquium ..........2222eeeeeeereerren een errerererreerreeere ern 273

Technical Seminars .........:.22ccseseenseeeeeeereneeeseneeeeeeeneeseeeneeeererteene 273

Theoretical Seminars ..........22cc2eeeeneeeeeeseeeneeeeereereeereeeeeeerererrereeene 274

TIS Seminar ........ 2222222 eeeeneeseeneseeeer nenne ereeter seen eeeererereerennenne 276

Training Programme 1994/95 .......2.seeeeeeeeeeeneneenennnenene 277

Academic Training ...........2e2cceeeeeseeesererereneeereererer ernennen eenereene 277

Technical Training .............22co2ocoeeseeeeeseeeneseeeeeeneesseeseneseerserteneenne 278

Management & Communication ........222eeeeereeeeeeeseeneeeeeernersneneeneeee nennen 281

Language Training ..........C222occeeeeeeneeeeeeeeeener een eeenereneren een eerenereens 282

Training Seminars .......2o2Coceeeeeeeeeeeeeereeereeerrer essen ereeeteneeeerneeens 283

General Education ..........-2e20eeeeeeeneerereeeenereeereerereneereneereeeeeererens 283

Training Organized Directly by the Divisions in 1994/95 . ..... 2.22 css ceeeeeeeeseeeeeeneee nen 283

Apprenticeships .........222eeeemeeeeeeeseeneeneeerereeerseereerseeeereeeereeeeteenen 283

CERN Schools .... 2 cc oc oo oo ee or een rer rer er rer er rer nn en nn 285

Accelerator School ........2....22cesseeeeeeeeneeeeeeenee seen een erer retten eeeenene 285

School of Computing ...........:22eeeeeeeeerenerenern error ner ee e nennen rnerrnene 287

1995 European School of High-Energy Physics ......... 22222 eeeeeeeeeeeener nern ereen nenne 288

Distinguished Visitors in 1995 .....2.2cceeoeeenereererneen nennen 289

Contents

Theoretical Physics Division

One of the major activities of the Theoretical Physics Division this year was the Workshop on Physics at

LEP2, held in close collaboration with the Particle Physics Experiments Division, and with the involvement of

many physicists from other European institutions. A detailed study of various theoretical problems was

performed, which, combined with the experimental contributions, produced a fairly complete handbook on the

physics of e* + e” annihilation above the WW threshold up to \s - 200 GeV. This included a separate volume

dedicated to the Monte Carlo event generators for LEP2 physics. In the framework of the Workshop, and upon

request of the Director of Research, a detailed interim report was produced on the physics interest of Phase IV

of LEP2, at that time not yet approved, which provided important scientific support for the final decision of the

CERN Council in December 1995.

In the general field of Standard Model physics, the main theoretical contributions of the Workshop focused

on precise calculations of WW cross-sections and distributions, on evaluations of the theoretical uncertainties

affecting different methods for the determination of the W mass, on cross-section calculations for the

background processes for the most interesting physics signals, and on possible tests of QCD much above the Z

resonance. Concerning the searches for new particles, a considerable amount of theoretical effort focused on

Higgs physics, both in the Standard Model and in its supersymmetric extensions: new results were obtained in

the calculation of the upper bounds for the Higgs masses predicted by different theoretical schemes, taking

into account the recent Fermilab determinations of the top quark mass, which allowed a better assessment of

the LEP2 discovery potential. The existing calculations of cross-sections and branching ratios for the new

particles predicted by supersymmetric extensions of the Standard Model were updated and completed when

necessary. Possible indirect signs of new physics at LEP2, appearing via anomalous triple gauge-boson

couplings, were also studied, taking into account the stringent constraints derived from LEPI precision data.

The interpretation of these LEP1 data continued to be one of the prime research activities of the Division.

Particular attention was devoted to finding possible theoretical explanations of the reported anomalies in R,

and R.. It was shown that these anomalies, as well as the excess of the jet rate at large transverse momentum

observed at CDF, can be explained as the effect of an extra heavy vector boson. Other explanations involving

supersymmetry were also considered. A new global fit to the precision electroweak data was presented and its

implications for the Higgs mass ınvestigated.

Another important area of research was the study of weak decays and heavy-flavour physics.

Phenomenological aspects of heavy quark production were studied within next-to-leading-order QCD to

obtain kinematical distributions for the production of top quark pairs at the Tevatron Collider, and the

differential distribution for heavy quark production at HERA. Soft gluon resummation effects in top

production and the production of charmonium states at high p, were also studied. The recent data from LEAR

on neutral kaon decays to n*n and tev were used to obtain upper limits on possible CPT-violation effects.


There was continued interest in deep inelastic lepton-nucleon scattering. These activities include the study

of polarized structure functions and the calculation of structure functions at small x using resummation

techniques. Theoretical studies were also performed on other aspects of perturbative and non-perturbative

OCD. In particular, a considerable amount of attention was given to the problem of renormalons: these are

non-perturbative ambiguities in the resummation of the perturbative series that play a role in the determination

of a, from Tlepton decay, e* + e” — jets, and other processes.

Lattice techniques were used by several theorists in the Division to compute physical quantities in QCD, in

particular the value of «,, and to perform numerical simulations of the electroweak phase transition at finite

temperature.

Members of the Division were also active in theoretical explorations beyond the Standard Model. The

problem of flavour was studied from the point of view of supersymmetry, supergravity, and string theory. The

possibility of dynamical determination of some of the associated parameters was examined. Other topics that

were considered included simultaneous Higgs and super-Higgs effects with flat potentials, and gauge-

mediated supersymmetry breaking. It was observed that scalars that are present in supersymmetric models

mediate macroscopic forces that could possibly be detectable with new techniques, such as those based on

small cryogenic mechanical oscillators.

In the area of cosmology considerable progress was made in deriving the observable predictions of a

model of inflation based on superstring theory. In particular, a stochastic background of gravitational waves in

the 100 Hz to 1 MHz region, with a large enough amplitude to be accessible to near-future (bar or

interferometric) detectors, is by no means excluded, while it is in the standard inflationary scenario. In the

interface of cosmology and astrophysics, the question of whether the Universe might contain large domains of

antimatter, antistars and antigalaxies is being thoroughly re-examined by members of the Division who have

also been involved in the writing of proposals for satellite observations aimed at improving our empirical

knowledge of the same question.

A considerable part of the scientific activities in the Division was devoted to fundamental aspects of gauge

theories, quantum gravity, and string theory. During the past year there were important new developments in

this area to which several theorists in the Division made very significant contributions. Central in these

developments was the notion of electric-magnetic duality, which provided a new and powerful tool to obtain a

qualitative and quantitative understanding of traditional issues in gauge theories such as confinement, chiral

symmetry breaking, and supersymmetry breaking. Using these ideas, new methods were developed at CERN

for doing exact non-perturbative calculations in supersymmetric gauge theories, as well as in supergravity and

superstring theories. These and other methods have been applied to calculate the quantum corrections to gauge

couplings and Yukawa couplings in four-dimensional superstring theories. A class of these models

successfully extend the Standard Model to a scale of o(10!? GeV). Other theoretical topics studied include the

physics of black holes, low-dimensional models of QCD and quantum gravity, and string theory in magnetic

fields. In November 1995 a successful workshop on the topic of duality was organized by the Division, with

about 50 participants from various European countries.

As usual, members of the Division were often consulted by their experimental colleagues in connection

with the programmes at CERN and other accelerator laboratories, and were active participants in experimental

and other committees. They were also called upon to speak at many conferences and workshops, and to lecture

at physics schools throughout the Member States and elsewhere.


Particle Physics Experiments Division

The LEP Programme

ALEPH

The ALEPH Collaboration (Annecy; Barcelona Auton. Univ.; Bari; Beijing; CERN; Clermont-Ferrand;

Copenhagen; Demokritos; Palaiseau Ecole Polytechnique; Edinburgh; INFN, Florence; Florida State; INFN,

Frascati; Glasgow; Heidelberg; Imperial College; Innsbruck; Lancaster; Mainz; Marseille; MPI-Munich;

Orsay; INFN, Pisa; Royal Holloway College; RAL; Saclay; Santa Cruz; Sheffield; Siegen; INFN, Trieste;

Washington; Wisconsin) is studying physics both at the Z peak and recently also at higher LEP energies. Its

general-purpose detector combines high-granularity electromagnetic and hadronic calorimeters with excellent

3-dimensional tracking. This allows accurate reconstruction of charged and neutral particles plus lepton

identification over almost the full solid angle.

During the 1994/95 shutdown, changes were made to ALEPH’s read-out electronics to accommodate LEP

running with bunch trains during 1995. This was successful, and during 1995 ALEPH collected 35.7 pb’! of

data in a three-point energy scan around the Z peak, together with 5.8 pb’! during a high-energy run at 130-

140 GeV. The overall data-taking efficiency was 91%, thanks in part to the very clean conditions in LEP

during the high-energy run.

The main upgrade to the detector during 1995 was the partial installation of a new two layer, double-sided

vertex detector (VDET) in October. The dectector is twice as long as the old one, thus increasing the VDET

angular acceptance to Icos BI < 0.95. Furthermore, its radiation thickness is a factor of three lower, which, by

reducing multiple scattering, should improve impact-parameter resolution and hence the b-tagging

performance. This will be important for Higgs searches at LEP2. A further advantage of the new VDET is its

use of radiation-hard read-out chips to resist the higher radiation levels expected at LEP2. Figure ALEPH-1

shows an event taken with the new VDET.

Physics Highlights

The highlight of 1995 was LEP’s high-energy run in November, during which centre-of-mass energies

of 130-140 GeV were achieved. Preliminary measurements of qq, e’e’, u’u” and T*T” cross-sections

were made, with direct production clearly separated from radiative returns to the Z, using cuts on invariant

mass or energy imbalance along the beam axis. vV’Yy events were also clearly seen. These results agree with

theoretical predictions and help constrain the contribution of Y-Z interference to the total cross-section.


Figure ALEPH-1 shows a radiative dilepton event recorded during this run. Searches for exotic final states

resulted in improved limits on charginos, neutralinos and selectrons. Compared with QCD predictions, an

intriguing excess of four-jet events was seen, in which the sum of the two-jet invariant masses peaked around

110 GeV/c*.

Fig. ALEPH-1: A radiative dilepton event recorded at a centre-of-mass energy

of 140 GeV. The hits produced in the new vertex detector can be seen.

During 1995, ALEPH published 24 papers based upon data taken near the Z peak, and made over

40 contributions to conferences. Furthermore, 24 students presented theses describing work done in ALEPH.

Some of the results are summarized below.

A comprehensive study of T decay modes was carried out, with most of the results improving on the

world average. The hadronic branching ratios were measured as a function of the number of charged tracks

and number of neutral pions in the final state. Further results were given for T decays to charged and

neutral kaons. The leptonic branching ratios were measured to be B.= 17.79 +0.12+0.06% and

Bu = 17.31 +0.11+0.05%. Combined with a new T lifetime measurement of 293.7 +2.7+1.6fs, these

results allow the universality of the lepton couplings to transverse W* to be tested: gu/8. = 1.0002 # 0.0051

and g,/g = 0.9943 + 0.0065. A measurement of T polarization versus polar angle was updated, giving

improved knowledge of the Z to lepton coupling: gy/gı = 0.0685 + 0.0075 for T and 0.0650 + 0.0086 for

electrons. Furthermore, an upper limit of 24 MeV/c? was placed on the v, mass. This was achieved using

Fig. ALEPH-2, which is a plot of visible energy versus invariant mass in T > 5-prong decays.


1.1

N ALEPH

Enad/Ebeam

Lu. nn. Sensitive region

0.95

09 Inner line: m, = 31 MeV/c? Outer line: m, = 0 MeV/c? 1 0 contour lines 0.85 L_ \ L

1.62 1.66 1.7 1.74 1.78 1.82

Mnaa (GeV)

Fig. ALEPH-2: The visible energy versus invariant mass of 25 T— 5-prong

decays. The solid lines show the kinematic limits for v„ masses of O MeV and

31 MeV/c? (the previous best limit).

B physics remains a very active area. A new measurement of the average b-hadron lifetime of

1.533 #0.013 + 0.022 ps was complemented by the exclusive measurements: Tg, = 1.54 0.07 ps

(preliminary), Tg-= 1.58 + 0.09 ps (preliminary), Tg, =1.59+0.15 ps and Tp_yaryon = 1.05 + 0.15 ps. The

last of these is below theoretical expectations. The lower limit on BO mixing was significantly increased to

Am, > 6.1 ps! using an analysis which tagged the initial and final states of the B, using jet charge and a lepton

tag, respectively. For the first time at LEP, a measurement of the CKM matrix element V., was made using the

decay BO>D+ 0-3 eg. The differential cross-section of this decay can be translated into a measurement of

V.p F(w), where F(®) is the form factor and ® is the Lorentz boost of the D** in the B° rest frame. (See

Fig. ALEPH-3.) At = 1, one obtains V.) = (34.5 # 4.0) x 107 using the theoretical prediction for F(1).

From measurements of the relative energies of the lepton and the neutrino in semileptonic A, decays,

ALEPH also gave a first measurement of the A, polarization, —23 # 23%, which is sensitive to the b-quark

polarization. Furthermore, using the decays B*—By and B** > Br, in which the B meson was

reconstructed using a topological search, the relative masses and production rates of excited B mesons were

measured. Finally, using semileptonic b decays, in which the energy of all the decay products was measured,

(using missing energy for the v), the most precise measurement to date of the b fragmentation function was

obtained. (See Fig. ALEPH-4.)

An analysis which separated uds, c and b events using lifetime and lepton tags found no dependence of the

strong coupling constant on flavour: ab / auudsc = 1.002 + 0.023 and auuıds / cd = 0.971 30.023. A lifetime

tag was also used in a comparison of quark- and gluon-jet properties. This showed that gluon jets are broader

and have higher multiplicities than quark jets. Preliminary results were obtained on the production rates of

baryons (3°, 30, £*, O7) and vector mesons [p°(770), @(782), K*%(892), #(1020)]. In yy events, D** production was observed at a rate compatible with theoretical predictions.

A search for supersymmetry was published, in which R-parity was assumed to be non-conserved (which

means that the lightest supersymmetric particle is unstable). Providing that the R-parity violating coupling is


dominated by leptonic fields, limits on supersymmetric particles were found to be at least as strong as when

R-parity conservation is assumed.

Preliminary measurements of hadronic and leptonic cross-sections and lepton asymmetries were

obtained using the 1994 data. In addition, the cc peak forward-backward asymmetry was measured to be

Ad, (c) =8.0+2.4% using high momentum D**. Fitting all ALEPH electroweak data to the Standard

Model yielded sin? 0° = 0.2319 + 0.0005, mz = 91.1924 + 0.0037 GeV/c?, Tz = 2.4951 + 0.0055 GeV and co) = 41.56 + 0.09 nb (preliminary).

ALEPH

2 om- v0 3 Fi

0.1] ------- Flo)lV

Fig. ALEPH-3: The product V,, F(w) for the decay BP >D* ı Vv„asa

function of @ the Lorentz boost of the D** in the B® rest frame. The curves show

a straight-line fit to the data before (dotted) and after (solid) convolution with the

detector resolution.

4 Ss 5 ALEPH

5351

< Peterson

3 L...... Kartvelishvili

....... Lund symmetric

251 ;

ar # 7

151 ZA

1! Fi

05L a

of rl bh

0 01 02 03 04 05 06 07 08 09 1 B energy fraction X.)

Fig. ALEPH-4: The measured energy spectrum of leading b hadrons, compared

with various fragmentation models.


DELPHI

The DELPHI Collaboration (Ames, Amsterdam, Antwerp, Athens, Bergen, Bologna, Bratislava, Brussels,

CERN, Copenhagen, Cracow, Dubna, Genoa, Grenoble, Helsinki, Karlsruhe, Lisbon, Liverpool, Ljubljana,

Lund, Lyon, Marseille, Milan, Mons, Orsay, Oslo, Oxford, Padua, Paris, Prague, Rio de Janeiro, Rome,

Rutherford, Saclay, Santander, Serpukhov, Stockholm, Strasbourg, Turin, Trieste, Udine, Uppsala, Valencia,

Vienna, Warsaw, Wuppertal) resumed detector operation in spring 1995 to measure the properties of the Z

boson and its decay products, especially the T lepton and heavy quarks.

During the yearly shutdown we continued to improve the DELPHI detector in two respects: the old Inner

Detector with its jet part and its trigger layer was replaced by anew and longer version. The jet chamber was

again provided by NIKHEF as in the past while the trigger layer was replaced by 5 layers of straw tubes built

by a collaboration from CERN, Liverpool and Cracow. The angular coverage went therefore from an original

30° down to about 15°. A further improvement was the implementation of a cathode read-out of the hadron

calorimeter performed by a collaboration from Dubna, Helsinki and Prague. The whole barrel part is now

equipped with this additional read-out, which gives much better granularity than before. The two end-caps will

be modified in the same way during the 1995/96 shutdown. In addition to these upgrades, a few detectors went

through minor modifications or repairs and, naturally, all other systems like the solenoid, ventilation, cooling

systems and safety devices were maintained as usual. All this has paid off as, from a technical point of view,

DELPHI ran very successfully and steadily throughout 1995.

In 1995 DELPHI completed the LEP1 phase by registering 750 thousand Z’s, including 236 thousand Z’s

taken off-peak during the scan period. In the first high-energy run of period P3, DELPHI registered - 3 pb’! of

data at energies of both 130 and 136 GeV.

The preliminary results of P3 concern all aspects of measurements and searches. Genuine high-energy

events are clearly separated from radiative-return events. Cross-sections and asymmetries of fermion-

antifermion channels are in good agreement with the Standard Model expectations. The study of single yand

single W channels allowed DELPHI to start putting bounds on anomalous boson couplings.

Lower limits have been set on the masses of most of the conceivable new particles. In particular charginos

are excluded up to - 56 GeV in the general case (one candidate), - 65 GeV in the specific and most difficult

case where the mass difference Am between the chargino and the LSP is small (5 <Am< 10 GeV/c?) (see

Fig. DELPHI-1). For an LSP of 30 GeVict, stop quarks are excluded up to - 43 GeV/c? (right? component)

and - 57 GeV/c? (‘left’ component).

In 4-jet final states no evidence is observed for pair production of heavy objects, although DELPHI cannot

exclude their existence at the level of cross-section of ALEPH’s claim.

For LEP1 physics much progress was made in most sectors. One of DELPHI’s recent papers, CERN-PPE/

95-194, illustrates the performance of the instrumental and analysis tools, which in all cases matches or

surpasses what was foreseen and still continues to improve, particularly with respect to performance in hadron

identification.


DELPHI Ecm = 130.4 + 136.3 GeV

o & E

3 - ® 10 m(v) = 1 TeV o }

ö ö n

07 | 5<My*-My? < 10.GeV

11 41 <m(v) < 100 GeV

|

10 bs shaban iu 45 475 50 525 55 57.5 60 625 65 675 70

Mx* (GeV)

Fig. DELPHI-1: The mass limit on charginos in the ‘degenerate’ case, when the

mass difference Am between the chargino and the LSP is small

(5 <Am< IO0 GeV/c? ) (preliminary).

51 papers were submitted to the Brussels conference. DELPHI sharpened its measurements of all

electroweak observables in fermion-antifermion final states. The heavy-quark asymmetries are

Afp= 0.0814 + 0.0104,

Ab, = 0.1066 + 0.0064 .

These last two measurements yield the value sin? 0% = 0.2306 + 0.0010.

DELPHI performed two original measurements: the interference between initial- and final-state radiation

in the u*u” channel and the transverse spin correlation in the T"t” channel. It is also the only experiment to

provide the ss App asymmetry, thanks to the RICH kaon identification:

Afp > 0.120 # 0.018 (stat) + 0.016 (syst).

R, was measured by DELPHI using three different methods:

RDELPHI - 0.2216 + 0.0016 (stat) + 0.0021 (syst),

with R. fixed to its Standard Model value (R. = 0.171). This does not agree well with the Standard Model

expectation; such a discrepancy was also observed by the other experiments.

DELPHI’s preliminary R. measurement is currently 1.5 0 below the Standard Model expectation: much

activity is underway, using several different methods and including all data, to improve this measurement and

the estimate of its error.


Thanks to the microvertex and to the RICH information, DELPHI pursued some high quality, and

sometimes pioneering, activities in t and heavy-flavour physics.

The 1 lifetime was measured to be t, = 290.7 + 3.6 fs. The ratio of the Fermi coupling constant for T decay

relative to that for muon decay is 0.991 + 0.009, compatible with lepton universality. Upper limits on lepton

flavour-violating decays were set to

Br(t>ey<1.1x10%

Br (t > uy) <6.2x 10° at90% CL.

The strangeness content of the T was studied (Fig. DELPHI-2). In the final states involving one or two

kaons DELPHI found:

Br [T>KTK*’r v, (neutrals)] = (0.22 + 0.04 # 0.01)%

[World average = (0.20 # 0.07)%]

Br[” >Kr’n v, (neutrals)] = (0.63 + 0.09 + 0.03)%

[World average = (0.43 +0.11)%] ,

and obtained the following ratios:

Br (KKv,) / Br (nv,) = 0.012 + 0.004

Br (KKrv,) / Br (anv,) = 0.014 + 0.003

Br (KK 2 2nv,) / Br (2 3nv,) = 0.008 + 0.004 .

These values imply that replacing an by a KK pair reduces the branching ratio by a factor - 0.012.

Veto identification (6.0 - 10.5 GeV/c)

125 FT |

Ring identification (8.5 - 25.0 GeV/c) e Observed

80 100 7 — Expeced — r

® aut 75L EG6OF 2 1. e

“& h 50 — _

8 a0, c >

5 5 | 257 -

2077 Kunit Li AR _ 0 | | | 2 . Lı Auttnc nn | u

0 5 0% 95 2 53 0% 35 4 0 5 10 15 20

Momentum (GeV/c) Number of photo-electron for r

Fig. DELPHI-2: Kaon identification in T decay from the RICH: ring

identification (left), veto identification (right).


In B physics much progress occurred in the field of B® oscillations. From the measurement of B}

oscillations, DELPHI extracted the precise value Amy = 0.421 + 0.040 ps’!. In the field of BO oscillations

DELPHT’s present limit is Am, > 4.6 ps! (Fig. DELPHI-3).

Preliminary

< E £ g (D,-)+(et- 4) DELPHI © E _ “175 channels (91-94 Data)

By: 12.5

10 E 75:

5; 25 F

09 Rn 1 Am, (ps”')

®

ER: < E

2 - h 4++6

0 fe as larlı., , | )+

ETTTERT TS t tr? -2 -

4, a

0 2 4 6 8 10 12 14

Am, (ps)

Fig. DELPHI-3: Am, determination from the (D,-£) and (Jet-£) channels

(preliminary).

A search for rare decays of the b quark in charmless hadronic, radiative and dineutrino modes was

performed using 3x 10° Z hadronic decays. Evidence for charmless hadronic decays of B mesons was

obtained by observing eight events in two-body modes. Branching ratios for BI, > (nn +K*n),

B%, > K*n and B, > (p n+ K*r) were derived. The fraction of events with a kaon in the final state

not due to the spectator s quark was measured to be 0. 6319.39 (stat). This value agrees with the expectation if

theb— sandb— u decay processes contribute almost equally to the observed hadronic charmless b decays.

Improved upper limits were set for B mesons decaying in final states with higher multiplicity and for the A,

DELPHI pursued its pioneering work in the new fields of B spectroscopy. The A, baryon was observed in

the At rn” and Atar channels. Its mass is 5668 + 16 (stat) #5 (syst) MevV/c?. For the =» DELPHI gave the

first indication of a signal and its first lifetime estimate in 1994 and now has an improved lifetime estimate:

tz, =1.349:37 +0.23ps (preliminary).

A most fruitful activity is the exploration of the excited B-hadron spectroscopy. For the B*, the B*/B

production ratio, the fragmentation function and the helicity structure were measured. The B**, B

(Fig. DELPHI-4) and the %&, and I, (the last two having been first observed in DELPHI) are under active

study. Overall the B system appears to be a very good approximation to the heavy quark limit (HQET model).


DELPHI Bt* > BK

rt

Counts/12

GeV

J 3

3 TTTTTTT

TITTEN

2 +

use

TTTTeTTTTTTITteteereTnn

PS an

TTITITTTS i | 4

sahen hs als ] dh sıli il

0 005 1 015 02 025 03 035 04 QABKYGeV

Fig. DELPHI-4: The B, * signal in DELPHI.

DELPHI members were very active in the various groups of common LEP activities: the LEP Energy WG

(in particular its chairmanship), LEP Electroweak Groups, Scan Steering Group. They also played a key role

in the recently completed LEP2 Workshop, both in the field of measurements (M,,, Triple Boson Couplings)

and searches (Higgs, SUSY). The authors of the now widely used SUSYGEN program are members of

DELPHI.

L3

L3 is a collaboration of institutes from Aachen I and III; NIKHEF, Amsterdam; Michigan, Ann Arbor;

LAPP, Annecy; Louisiana State Univ., Baton Rouge; Johns Hopkins, Baltimore; IHEP, Beijing; Humboldt,

Berlin; INFN, Bologna; Tata, Bombay; Boston; Northeastern; Bucharest; KFKI, Budapest; Harvard and MIT,

Cambridge; CERN; INFN, Florence; Geneva; Hamburg; Hefei; Helsinki; Lausanne; Los Alamos; Lyon;

Madrid; INFN, Milan; ITEP, Moscow; INFN, Naples; Cyprus, Nicosia; Nijmegen; Oak Ridge; CALTECH,

Pasadena; INFN, Perugia; Princeton; INFN, Rome; St. Petersburg; UC, San Diego; Santiago de Compostela;

Sofia; Taejon, Korea; Taiwan; Alabama, Tuscaloosa; PSI, Villigen; Purdue, West Lafayette; World Laboratory;

DESY, Zeuthen; ETH, Zurich; Basle Univ.; and Utrecht Univ.

L3 was designed as a general-purpose detection system with an emphasis on the measurement of electrons,

photons, muons and jets produced in e*e” annihilation with good spatial and energy resolution.

During the 1994-95 shutdown we completed the forward-backward muon detection system; installed a

new active lead ring in the polar angle between the end-cap BGO calorimeters and the luminosity counter;

upgraded the level-2 trigger and commissioned a bunch-tagging trigger and read-out system to allow operation


in bunch-train LEP running. All these new components functioned well during the 1995 running and were

fully operational for the data taken this year.

During the current shutdown (1995-96) we carried out a major intervention on the central detectors. This

was necessitated by the installation of the new vacuum pipe, masks and shielding for LEP2 operation. In order

to precisely align the central detector to this new beam pipe, we removed all end-cap detectors to give full

access to the TEC (central tracking chamber). We took advantage of this access to install a new detector, called

the EGap calorimeter. This calorimeter fills all 6-pointing cracks in the region between the BGO barrel and

end-cap calorimeters (8 cracks are non-pointing); it also makes the energy measurement hermetic even for

photons down to 1 GeV, and is important for LEP2 searches where missing energy plays an important role in

many of the proposed signatures.

We are also installing a VSAT (Very Small Angle Tagger) to allow tagging of two-photon interactions

down to an angle of 4 mrad. This completes the L3 detector for LEP2 running.

In 1995 we accumulated an integrated luminosity near the Z peak of 30.1 pb!. In the final running period

of 1995 we accumulated 5.1 pb-! at centre-of-mass energies around 130-140 GeV. For essentially this entire

data sample, all L3 sub-detectors were fully operational and performing at their nominal resolution and

efficiency. A new dedicated SGI multiprocessor allowed us to fully reconstruct all data in almost real time,

making use of high-speed fibre-optic communications between the data acquisition system and the off-line

reconstruction. This was particularly important during the high-energy running where we were able to both

confirm proper operation of the detector and perform most of the searches for new physics within hours of

data being taken.

Some of the most interesting results we published in 1995 are outlined below:

— Using energetic single photon events, we set an upper limit of 4.1 x 10° Up (90% CL) on the magnetic

moment of the T neutrino.

— Using the precise energy measurement of the calorimetry, we were able to study the neutrino energy

distributions in b-quark decays, and by comparing them with the charged leptonic decays, we

found the W* polarization to be well described by that obtained from a free b-quark decay model with

a (V-A)x (V-A) decay structure. Alternative decay structures such as (V+A) x (V-A) are strongly

disfavoured.

— We used photon final-state events to study QED processes and to search for deviations from QED, for

example setting a limit on the mass of an excited electron: m.x > 146 GeVic*.

- In two-photon processes we studied the reaction ete” — e*e” Y’y' —e*e” KO KO. We observed the

formation of the f} (1525) resonance and measured its radiative width times branching ratio. The

31 candidate events are found to be consistent with the f, being a pure helicity-2 state. We also

observed a second peak at 1793 MeV/c? shown in Fig. L3-1. The second peak has a statistical

significance of only 2.9 standard deviations at this time. We expect to continue the study of this and

similar systems at LEP2, where the relative rate of two-photon events compared to the Z event

‘background’ is much higher.


— We searched for rare B decays involving photons, neutral pions and eta mesons, obtaining for example

Br(B, > nm)<25x10%,

Br(B, > nn?)<10x10°,

Br(B, > W<39x 10°,

Br(B, > m<15x10%.

— Inthe 95c running period when LEP ran at centre-of-mass energies around 130-140 GeV, we measured

the production of hadrons and lepton pairs together with the lepton pair forward-backward

asymmetries. Including also the data from Z running, where we use the presence of strong initial state

radiation in some u*’w(y) final states to calculate a reduced effective centre-of-mass energy, we

obtained the results shown in Fig. L3—.

— We observed the evolution of a, with Ns, obtaining the result a, (133 GeV) = 0.107 + 0.005 (exp)

+ 0.006 (theor).

— Using the period 95c data, we searched for many new physics states, observing none. We set, for

example, the limits shown in Fig. L3-3 in the chargino-neutralino mass plane.

L3 is ready for LEP2 operation.

15 T T v T 1 v T v I

L3

Pr

> 10r _ © L = @ fr 3 | S >

u sr =

( ! / a, 10,09

11111] l.....| INTEL I} | 0 III I LT Isis l ‚il$ ı$ ı del.ddh

1.0 1.5 2.0 2.5

KO KO mass (GeV)

Fig. L3-I: KOK° invariant-mass plot in ete >e*e” YYy>e+e KO K?

events.


| T ]

| L3 1 i 60 > UL Yısr 3

= 1 ee yy)

E | N 1 a 17

T 1 In 4 % 4

5 102 ; * CELLO | # JADE | * MARK) A AMY leHRS »PLUTO D TOPAZ | MAC 0 TASSO Oo VENUS

103 1 ’ | T |

L3

= 68 > {UL Yısr 0.5 ee > 1u(y)

= =

T 0 - | o

&

-0.5 - x CELLO - * JADE

| * MARK) A AMY sHRS »PLUTO CTOPAZ

4. MAC 0 TASSO © VENUS

5 100 150

Ys [GeV]

Fig. L3-2: Cross-section and asymmetry for ete > u" as a function of vs.

MyG > Mi! MV > 200 GeV = | nu ©

° = 60- -

40 ar _

«©

3 z B

‘2

3 204 3 | Excludedat95 %C.L. -

u Pure Higgsino

0 T ’ 40 50 60 70

My: (GeV)

Fig. L3-3: Excluded region in the chargino and neutralino mass plane.


OPAL

The OPAL Collaboration consists of groups from Aachen; Univ. of Alberta; Birmingham; INFN, Bologna;

Bonn; Brunel; RMKI-KFKI, Budapest; Cambridge; Carleton; CERN; Chicago; ATOMKI, Debrecen; DESY,

Hamburg; Duke; Freiburg; Heidelberg; Indiana; Kobe; QMW, London; Manchester; Maryland; Montreal;

Oregon; CRPP, Ottawa; RAL; Saclay; Technion; Tel Aviv; Tokyo; TRIUMEF, Vancouver; Victoria; Univ. of

B.C.; UCL; UC Riverside; and Weizmann Institute.

The general-purpose OPAL detector is used for a wide range of physics studies. In 1995 OPAL recorded

730 000 multi-hadronic Z decays, bringing the total number of visible Z’s which OPAL has recorded at LEP1

to 5.1 million. In addition, an integrated luminosity of 5.6 pb! was recorded at LEP energies between 130 and

140 GeV.

Detector Upgrades

During the shutdown at the beginning of 1995, the OPAL beam pipe was modified to allow the installation

of masks to provide improved shielding from the background of synchrotron radiation expected at higher LEP

energies. This also solved a problem concerning the space requirements for the installation of the upgraded

silicon microvertex detector. The superconducting quadrupoles of the low-ß insertion were replaced with the

set of second generation quadrupoles designed for use at LEP2. At the same time, modifications were made to

the silicon-tungsten luminosity monitor to allow it to trigger efficiently on each individual bunch crossing

under bunch-train operation, and thus enable the systematic error on the luminosity measurement to be

maintained at less than 1 part in 1000.

The silicon microvertex detector was re-installed with the addition of one layer of its planned extension.

This upgrade will be completed at the beginning of 1996, and will provide OPAL with an increase in its

longitudinal acceptance in time for the higher-energy running of LEP.

The design of the scintillating tile detector for the end-cap regions of OPAL was completed in the course

of 1995. This detector is designed to enhance the triggering information available in the forward region and to

be compatible with bunch-train operation. Tests with cosmic rays and test beams have shown that the detection

of single ionizing particles will be achieved with the required high efficiency. All of the scintillator has been

cast and cut to shape, and delivery of the multi-cathode phototubes is foreseen for early in 1996. The assembly

of this detector is being carried out during the 1995-96 shutdown, and it will be installed in time for data

taking in 1996. This installation has necessitated a modification to the end-cap presampler.

The OPAL online electronics were modified in 1995 to permit efficient triggering and data read-out during

bunch-train operation.

Physics Results

In 1995 the OPAL Collaboration published or had accepted for publication 32 papers. Many additional

results were presented to conferences throughout the year, with 24 papers being submitted to the major

summer conferences. Over 40 internal reports on physics results were prepared.


OPAL analyses were performed in nearly every area of LEP physics, from electroweak physics, heavy-

flavour physics, T physics and QCD to searches for new particles and phenomena. As in previous years,

students contributed heavily to the physics output of the experiment, and 48 theses were completed

during 1995.

Electroweak Physics

The large amount of Z data collected in 1994 on the peak of the resonance was used to improve the

determination of the Z line-shape parameters. The partial width P,5/IUnaa was updated using a lifetime

double-tagging method. A modified double tag and a charm counting method were applied in two new

measurements of T'.c/Tyag. The measurements of the heavy-flavour asymmetries were repeated, using

leptons, a jet-charge technique and D mesons. OPAL played an important role in combining all LEP

electroweak data for the major conferences. Overall very good agreement with the Standard Model was

observed. Only T,5/Tnag and Te /T'nag seem to show a discrepancy with the predictions of the Standard

Model (Fig. OPAL-1).

R. 0.18 ITTTTTIERMIITTTTTT

m L

0.1778 r I

l

| 1

0.16 \ \ \

0.15 Fr N \

0.14 F N

| N OPAL preliminary\_ | 0.13 u

0.214 0.218 0.222 0.226

b

Fig. OPAL-1: Contour of T,5/I nad versus T’.z /Inad - Shown are the results

of the OPAL experiment (star), the 68% and 95% confidence limits and the

prediction from the Standard Model for three different values of the top mass.

Heavy-Flavour Physics

The lifetimes of nearly all species of B hadrons could be measured or the measurement be improved based

on the large amount of data available. In particular, a determination of the lifetime of the A, was possible

using A lepton correlations. There now seems to be evidence that the b-baryon lifetime is significantly lower

than theoretically expected. OPAL also updated its determination of the lifetime of the B° and B* states, which

are, as expected, nearly identical.

An improved determination of the B-meson oscillation frequency was achieved using dilepton events.

From these events and from & lepton and D, lepton correlations, limits could be set on the B,B, mixing

strength.


The production of charmed mesons has been studied in great detail both in cc and in bb events. The

previously published measurement of charm-quark production in gluon jets was improved using a lepton tag

together with a topological event selection.

Tau Physics

Many aspects of the physics of the T lepton were studied. A number of hadronic and non-

hadronic branching ratios were newly measured or updated. The hadronic decay current of the T was studied

int nn nv, decays. Possible deviations from the exponential decay law were investigated in T decays.

The lifetime of the T lepton was updated using all available data, allowing tighter limits to be set on lepton

universality (Fig. OPAL-2).

300

298 F

t li

feti

me

(fs)

296 |

294 | 292 |

290 |

288 | 286 F

284 [

uf

i. l Lı |, l 289 sul su 1... lu 172 174 176 178 18 182 184

Bow (%)

Fig. OPAL-2: Contour plot of the branching ratio T— evv versus the T lifetime.

The point with error bars is the OPAL measurement; the grey area indicates the

range of predictions from the Standard Model if ut universality is assumed. The

width ofthe area reflects the uncertainty on the T mass measurement.

Particle Production Rates

A large number of different particle production rates were measured in 1995. These analyses often took

advantage of the excellent particle identification properties of the OPAL detector. Rate measurements were

made for the heavy mesons: Y, J/y, D,, D°, D* and A**. The rates and properties of the strange vector mesons

[6 (1020), K*(892), K,(1420) and K°] were studied.

OCD Studies

Many analyses in the QCD sector took advantage of the well understood capability to tag different

flavours. Results were obtained from a model-independent analysis of the difference between quark and gluon

jet properties, for the first time carried out with flavour-tagged samples, both for light and heavy quarks.

Lifetime information is used to isolate a sample of beauty tagged events, high momentum stable particles

provide a means of identifying light flavour events. In both analyses, gluon jets proved to be somewhat

broader and softer than quark jets.


A number of studies of fragmentation functions were performed, both for inclusive charged particle

spectra and for beauty quarks. The multiplicity of charged tracks was measured in both beauty and charm

samples.

Searches

OPAL updated its charged Higgs-boson search, both in the framework of the Standard Model, and of

supersymmetry. Searches were also performed for heavy charged particles. A new limit was set in a search for

lepton flavour violation. Using isolated photons a search was performed for a narrow resonance in decays of

the Z.

First Results from High-Energy Running

Only a few weeks after the end of LEP 1.5 running OPAL presented first results from e*e” collisions at

130-140 GeV. A search was performed for charginos and neutralinos: no candidates were found, and new

mass limits could be set. The Standard Model physics was probed using the higher energies. Cross-sections

and lepton asymmetries were measured and found to be well described by the expectations (Fig. OPAL-3).

Inclusive properties of the events, e.g. charged particle multiplicities, were studied and compared to lower-

energy measurements. A number of interesting events were found in the four-fermion final state, with a rate

somewhat higher than expected.

ee*e” > hadrons o @*g” > hadrons; s’/s> 0.8 .e'e > ete’; Icoshel<0.7; 4 4 Sacol<10 -

see „uU

oete > urn; s’/s > 0.8 “ee JTT were” + tr, 8’/s>0.8

10°

cros

s-se

ctio

n / pb

3 r

s/s>0.8

10° }

10!

x 0.1 ie BE

IF s/6 >08. = 2 Tu I. 1. ı ih l j l Lo ı ı 1 } }

60 80 100 120 140

\s/GeV

Fig. OPAL-3: First results for the total cross-section of electron-positron

annihilation at highest available energies. The plot shows different channels, as a

function of the centre-of-mass energy vs. At the high energies (around 130 GeV),

measurements are shown for events without a significant loss of energy due to an

initial-state photon (s/s > 0.8), and for all events. The points are the

measurements, the curves are the predictions from the Standard Model.


The LHC Programme

ATLAS

ATLAS is a general-purpose experiment for recording proton-proton collisions at the LHC. The ATLAS

Collaboration consists of 147 participating institutions (December 1995) with more than 1500 physicists and

engineers (650 from Non-Member States). The detector design has been optimized to cover the largest

possible range of LHC physics: searches for Higgs bosons and alternative schemes for the spontaneous

symmetry-breaking mechanism; searches for supersymmetric particles, new gauge bosons, leptoquarks, and

quark and lepton compositeness indicating extensions to the Standard Model and new physics beyond it;

studies of the origin of CP violation via high-precision measurements of CP-violating B-decays; high-

precision measurements of the third quark family such as the top-quark mass and decay properties, rare decays

of B-hadrons, spectroscopy of rare B-hadrons, and BO -mMIXing.

The ATLAS detector, shown in Fig. ATLAS-I1, includes an inner tracking detector inside a 2 T solenoid

providing an axial field, electromagnetic and hadronic calorimeters outside the solenoid and in the forward

regions, and barrel and end-cap air-core-toroid muon spectrometers. The precision measurements for photons,

electrons, muons and hadrons, and identification of photons, electrons, muons, T-leptons and b-quark jets are

performed over |n] < 2.5. The complete hadronic energy measurement extends over |n| < 4.7.

Muon detectors

Barrel toroid

Electromagnetic calorimeters

Inner detector

Forward Solenoid

calorimeters

Hadronic

calorimeters

Fig. ATLAS-I: The ATLAS Detector for the LHC.


The inner tracking detector consists of straw drift tubes interleaved with transition radiators for robust

pattern recognition and electron identification, and several layers of semiconductor strip and pixel detectors

providing high-precision space points. During 1995, a decision was taken to construct the forward precision

tracking layers out of semiconducting detectors as in the barrel part. A broad programme of R&D and

prototype activities has been pursued. In particular, a full-size prototype wheel of the forward straw tracker has

been built.

The electromagnetic calorimeter is a lead-LAr sampling calorimeter with an integrated preshower detector

and a presampler layer immediately behind the cryostat wall for energy recovery. During 1995, extensive

optimization of the layout was performed and the design was frozen. For instance, an option for the use of LKr

for the barrel calorimeter was not retained following cost-versus-performance arguments. The end-cap

hadronic calorimeters also use LAr technology, with copper absorber plates. The end-cap cryostats house the

electromagnetic, hadronic, and forward calorimeters (tungsten-LAr sampling). The barrel hadronic

calorimeter is an iron-scintillating tile sampling calorimeter with longitudinal tile geometry. For all the

calorimeters, intensive test beam programmes with prototype modules have been continued.

The air-core toroids have undergone a thorough design-to-cost optimization. Eight superconducting coils

with warm voussoirs are proposed, with a bending power reduced by 15% compared to the Technical Proposal

specifications, together with slightly decreased overall dimensions of the muon spectrometer. The full ATLAS

detector potential for the measurement of final states such as the Higgs boson decay to four leptons is

maintained essentially at the level presented in the ATLAS Technical Proposal. The toroids will be

instrumented with Monitored Drift Tubes (Cathode Strip Chambers at large rapidity where there are high

radiation levels). MDT and CSC prototype measurements have achieved the required resolutions. The muon

trigger and second coordinate measurement for muon tracks are provided by Resistive Plate Chambers in the

barrel and Thin Gap Chambers in the end-caps; both kinds of detector have good time resolution. An ATLAS

RPC trigger tower model was operated in the beam for tests with non-flammable, environmentally friendly

new gas mixtures, and for trigger processor tests.

The ATLAS trigger scheme is a three-level trigger and data-acquisition system. The first-level trigger

signatures are: high-pr muons, electrons, photons, jets, and large missing transverse energy. For low-

luminosity operation of the LHC, a low-pr muon signature will be used in addition. At levels two and three,

more complex signatures will be used to select the events to be retained for analysis. As a result of an overall

cost-optimization, the upper limit on the level-1 output rate has been slightly reduced, resulting in diminished

bandwidth requirements in the detector readout systems and the DAQ, while still keeping a safety margin with

respect to the calculated trigger rate.

During the past year, the ATLAS Collaboration has put much effort into shaping its management structure.

The Executive Board has started functioning. The first ATLAS Resource Review has taken place. The LHC

Committee and the Research Board have recommended approval of the ATLAS project, together with the

plans, including milestones, leading to subsystem Technical Design Reports.

The next two years, 1996-97, will be the initial period covered by an Interim Memorandum of

Understanding. The emphasis will be on full-size prototyping, and detailed Technical Design Reports will be

provided to the LHCC for the subdetector systems.


CMS

The CMS Collaboration consists of 1303 members from 134 institutes in 30 countries. The Technical

Proposal, submitted to the LHC Committee in December 1994, was approved in 1995 by the LHCC and the

CERN Research Board.

Much progress has been made over the last year in studying the performance of close to final prototypes of

many subsystems and some details are given below.

Magnet

The detector will be built around a long (13 m) and large bore ($ = 5.9 m) high-field superconducting

solenoid (4 T). Small lengths of the reinforced conductor have been fabricated using different methods. A

team from CERN and CEA Saclay has been set up for the final design of the magnet coil. Potential suppliers

for the magnet return yoke are being identified.

Inner Tracking

All high-p, muons, isolated electrons and charged hadrons, produced in the central rapidity region, are

reconstructed with a momentum precision of Ap,/p; = 0.005 + 0.15p, (p, in TeV). Major advances have been

made in identifying operating conditions for recently developed microstrip gas chambers (MSGCs) that will

allow a long lifetime in the harsh radiation environment of the LHC. A refinement of the MSGCs, the

microgap gas chambers, providing stereo information, have been successfully tested in beams. Work is now

going on to industrialize the manufacture of MSGCs. Promising results have been obtained on several types of

silicon microstrip detectors including double-sided ones. Functionally complete radiation-hard front-end

electronics chips have been tested and good progress has been made towards the final system. Different

readout schemes for the pixel detectors are being developed and compared aiming at a final choice by the end

of 1997.

Muon System

Centrally produced muons are identified and measured in four identical muon stations (MS1-MS4)

inserted in the return yoke. Each muon station consists of 12 planes of aluminium drift tubes. A large

prototype (0.64 x 1.0 m?) consisting of two sets of 4-plane drift tubes with an improved field shaping was

tested with excellent results (single hit resolution of = 200 um). Each of the four end-cap stations (MF1-MF4)

consists of six planes of Cathode Strip Chambers (CSCs). Each CSC consists of six planes and a 0.6 x 0.6 m?

prototype yielded a timing resolution of = 3 ns and a point resolution of better than 200 um.

A second, fast and redundant, first-level trigger is provided by Resistive Plate Chambers (RPCs).

Considerable progress has been made in adapting the design of these chambers for long term operation under

LHC conditions where a high hit rate of several kHz per cm?

and a final choice will be made at the end of 1996.

is expected. Novel designs were tested in 1995


Calorimetry

Several prototypes of the electromagnetic calorimeter (ECAL), consisting of lead tungstate (PbWO,)

scintillating crystals, were tested in 1995. The performance goal of an energy resolution of better than 0.6% at

100 GeV was achieved for electrons (see Fig. CMS-1). Avalanche photodiodes were used to detect the

scintillation light and the response to ionizing radiation of these diodes was also considerably reduced.

Substantial progress has been made in the growth of PbWO, crystals especially by the Bridgman method.

2.25 I ı u T I \ ' I I

July II 95 2, CRYSTAL 1055 -

tower 7, runs 2600-2623 15H 4. mm x 4 mm beam spot u

noise (ped. in spill) subtracted

157 o First APD ” op/E= 4.25% JE ® 0.33%

21.25} © Second APD - < a op/E= 4.25% VE ® 0.39% 8 Ir Ne a Both APDs -

NS, op/E= 3.6%/ VE © 0.35%

0.75r

05 +

0.25} u | j | | | | | l | ©

0 20 40 60 80 100 120 140 160 180 200

E=X9 (GeV)

Fig. CMS-1: Energy resolution as a function of energy measured for electrons

incident in a4 x 4 mm? region in the centre ofthe 3 x 3 crystal array.

The ECAL is followed by a copper/scintillator sampling hadronic calorimeter. Test beam work in 1995

was targeted towards a better understanding of the detailed design of the hadron calorimeter in the barrel and

end-cap regions. Tests were also conducted with lead tungstate crystals placed in front of the hadron

calorimeter. |

A calorimeter with quartz fibres laid in grooves in copper plates was chosen for the very forward region

(pseudorapidity coverage between 3 and 5). Extensive beam tests were carried out on full-size prototypes of

the two possible designs, the other one being iron/gas filled parallel plate chamber sandwich. A detailed

comparison of the two designs was made prior to the choice,

Trigger and Data Acquisition

The conceptual design of the trigger processor and the data-acquisition systems was completed in 1995.

Some basic functions of the trigger processor were submitted for prototype production. A medium term

programme of prototyping of all the subcomponents has been initiated.


ALICE

The heavy-ion detector ALICE (A Large Ion Collider Experiment) has emerged as a common design by

the heavy-ion community currently engaged at CERN, and a number of groups new to this field from both

nuclear and high-energy physics. The Collaboration currently includes 565 physicists from 63 institutions in

26 countries.

ALICE is a general-purpose heavy-ion experiment, sensitive to the majority of known observables

(including hadrons, electrons, muons, and photons), and it will be operational at the start-up of the LHC. The

experiment will measure the flavour content and phase-space distribution, event by event, for a large number

of particles whose momenta and masses are of the order of the typical energy scale involved (temperature =

Aocp = 200 MeV). It is designed to cope with the highest particle multiplicities anticipated for Pb-Pb

reactions (dN/dy = 8000).

ALICE was first proposed as a central detector in 1993 and complemented early in 1995 by an additional

forward muon spectrometer. The Technical Proposal for the central detectors was submitted in December 1995

and an addendum to this Technical Proposal for the muon arm will be submitted before the end of 1996.

The overall detector layout is shown in Fig. ALICE-1. The central part, which covers +45° (In|< 0.9) over

the full azimuth, is embedded in the large magnet of the L3 experiment, left in its present position centred

slightly above LHC beam height. The experiment consists (from the inside out) of an inner tracking system

(ITS) with six layers of high-resolution silicon tracking detectors (pixel, drift and double sided microstrips), a

cylindrical TPC, and a large-area PID array of TOF counters (PPC or Pestov counters). In addition, there are

two small-area single-arm detectors: an electromagnetic calorimeter (PHOS) made from about 30 000 PPWO,

crystals and an array of RICH counters optimized for high-momentum inclusive particle identification

(HMPID).

! I in Peaen \ ! EZ Dnge er I: Para Be db. REST Pr ae PR BI Sn FR Sl nn ri, Kin

Rn EL Ha Sa, En we . ur} ! { ws A NR n ? r

NEN ir? REG ir:

- ! 4

x ;

a © MUONCHAMBER

Fig. ALICE-I: The ALICE detector for heavy-ion collisions at the LHC.


The forward muon spectrometer consists of a composite absorber (= 10 A) starting one metre from the

vertex, which is made with layers of both high and low Z materials to reduce multiple scattering and particle

leakage. It is followed by a large dipole magnet with 3 Tm field integral placed outside the L3 magnet, and ten

planes of thin, high-granularity tracking stations. A second absorber (= 11 A of iron) at the end of the

spectrometer and two more tracking planes are used for muon identification and triggering.

The spectrometer is shielded throughout its length by a dense absorber tube of about 60 cm outer diameter,

which surrounds the beam pipe at small radii. The set-up is completed by a set of zero-degree calorimeters

(ZDCs) located far downstream in the machine tunnel and a forward multiplicity detector (FMD) covering a

significant fraction of the phase space (n] < 4).

The SPS Fixed-Target Programme

Muon Experiments

NA47

The NA47/SMC experiment (Spin Muon Collaboration: Bielefeld, Bochum, CERN, Freiburg, GKSS

Helsinki, Houston, Istanbul, JINR Dubna, Mainz, Mons, Munich, Nagoya, NIKHEF, Northeastern,

Northwestern, Rice, Saclay DAPNIA, Santiago, Tel Aviv, Trieste, UCLA, Uppsala, Virginia, Warsaw, Yale)

investigates the internal spin structure of the nucleon through polarized deep inelastic scattering of muons by

protons and deuterons. Combining our measurement of the spin-dependent asymmetries A1(&,Q%) in the case

of longitudinal beam and target polarizations, together with earlier measurements of the spin-independent

structure functions F(x,Q°), we determine the spin structure functions g; for the proton, deuteron, and

neutron.

In 1992 data were taken on A, with a deuteron (butanol) target and a muon beam energy of 100 GeV

(3.2x 10° events). A muon beam energy of 190 GeV was used the following years which allowed the

coverage of the range 0.003 <x < 0.7 with a momentum transfer Q* > 1 GeV?. Data were taken on A| with a

proton (butanol) target in 1993 (4.4 x 106 events) and with a deuteron (butanol) target in 1994

(6.0 x 106 events) and in 1995 (8.5 x 106 events). In 1995, data were also taken on the asymmetry A, obtained

with transverse deuteron spin (2.3 x 10° events).

From the 1994 data, the deuteron structure function is found negative at smallx. The first moment

evaluated at Qu = 10 GeV? is T,‘ = 0.034 + 0.009 (stat.) + 0.006 (syst.). This value is below the Ellis-Jaffe

prediction by three standard deviations. It confirms with an improved accuracy our deuteron result obtained

in 1992 and also agrees with recent E143 data. Using our earlier determination of T'jP, we obtain TP - Tr? =

0.199 + 0.038, which agrees with the Bjorken Sum Rule. The fraction of the nucleon spin due to quark and

antiquark spins is A& = 0.20 0.11 and the fraction of the spin due to the strange quarks and anti-quarks is

As =-0.12 + 0.04.

Analysis of the 1995 deuteron data for both the A, and the A, asymmetries should be completed in

spring 1996.


Neutrino Experiments

WA95

The existence of non-vanishing neutrino masses and neutrino mixing will have profound implications in

particle physics and cosmology. The objective of the WA9S/CHORUS experiment (Amsterdam, Adana,

Ankara, Bari, Berlin, Brussels, CERN, Changwon, Chonnam, Ferrara, Gyeongsang, Haifa, Istanbul, Louvain,

Moscow, Munster, Naples, Rome, Salerno, Aichi, Gifu, Kobe, Kinki, Nagoya, Osaka, Toho, Utsonomiya,

Yokohama) is to search for neutrino oscillations in the tau neutrino appearance channel in the SPS wideband

neutrino beam. The experimental set-up consists of an emulsion target with a total mass of 800 kg, a

scintillating fibre tracker system, trigger scintillators, an air-core magnet, a calorimeter based on the

‘spaghetti’ technique, and a muon spectrometer.

Candidate Charm Kink

Candidate for: v,‚N > u"D* X

Y Yut Köv,

(a)

W u) 50 0 500 1000 1500

Fig. WA95-I: (a) A neutrino event recorded by the CHORUS detector, (b) with

semileptonic charm decay seen in the emulsion.

The CHORUS detector was completed on schedule in April 1994. The SPS neutrino beam was rebuilt and

optimized for the physics potential of the experiment. Physics data taking was conducted from May till

October 1994 and from May till October 1995. The expected detector hardware performance was achieved. In

total 2x 101? protons on target were delivered and about 400 000 neutrino interactions in the emulsion target

were recorded on tape. At the end of the 1995 run the emulsion target was removed and developed. One

quarter of the target with about 30 000 events was already exchanged after the 1994 run. These events have

been fully analysed and the process of emulsion scanning is in progress. About 10 000 events have been


located in the interface emulsion sheets and the primary vertex is now being measured. The novel technique of

fully automatic emulsion scanning is used to reduce the scanning time. First events with secondary vertices

(kinks) have been found and confirm the technical ability to detect tau neutrino interactions. One of the events

with such a topology is shown in Fig. WA95-1. The kinematical analysis of the event favours the

interpretation of v,N > +D"+X;D’>yu*+ KO +v,.

In 1996 the full analysis of the data taken in 1994/95 will continue. In parallel, data taking with a fresh set

of emulsions for another two years will start in April 1996. The R&D project of an active target based on glass

capillaries filled with liquid scintillator was continued with the exposure of the target in the neutrino beam and

a combined data analysis with CHORUS. |

WA96

The aim of the NOMAD experiment (Ambherst, Annecy LAPP, Calabria, CERN, Dortmund, Dubna JINR,

Florence, Harvard, Johns Hopkins, Lausanne, Melbourne, Moscow INR, Padua, Paris 6 & 7, Pavia, Pisa,

Saclay DAPNIA, Sydney ANSTO, UCLA, Zagreb) is to search for the oscillation v, > v, in the CERN

neutrino beam by looking for the appearance of T’s from v, charged-current interactions which are selected by

kinematical criteria. This is possible in the detector which precisely measures and identifies all the particles

produced in an interaction.

The detector was completed in 1995 with the addition of a hadron calorimeter and of a forward

calorimeter. About 300 000 events have been collected, a typical event is displayed in Fig. WA96-1.

Preliminary analyses show a good agreement between data and Monte Carlo simulations concerning muons,

electrons and hadron productions. Evidence for v. charged-current interactions is found.

Fig. WA96-I: A neutrino interaction reconstructed in the NOMAD target.


CP Violation

NA48

The goal of the NA48 experiment is to measure the parameter Re(e’/e) which characterizes CP-violation in

the neutral kaon system to a precision of 2x 10. The highlights of the activities for 1995 were the

installation and commissioning of the detector elements needed for the charged decay, and the preparation and

assembly of the liquid krypton calorimeter. In 1996, the calorimeter and its associated electronics will be

completed and commissioned in the beam line, thus completing the installation of the experiment.

The preparation of: the experiment passed a major milestone in 1995 by operating the charged-particle

spectrometer successfully and being able to reconstruct the charged CP-violating decay of the K-long particle.

Three of the four drift chambers and their associated readout electronics were installed in the experimental

zone (which is in the North Area high intensity facility in ECN3), joining the magnet which was installed

in 1993. The hadron calorimeter, tagger, hodoscopes, veto-counter systems, first-level triggers, and charged

second-level trigger were also operated successfully in the beam. The readout electronics for the experiment is

of a modern pipelined design and is a crucial part of the experiment as it has to cope with the very high rates

needed to make the €’/e measurement. The principle of this method of readout was proven in the 1995 beam by

handling triggers and reading out several of the subdetectors with the scheme. A new concept in data

collection was also tested and was very successful. Instead of writing tapes at the experiment, the data were

transferred over a link to the computing centre where they are temporarily stored in a high performance

parallel machine (the Meiko-CS2) and later recorded to tapes.

Rapid and steady progress was made in 1995 on the construction of the liquid krypton electromagnetic

calorimeter which is used to reconstruct the K > nn? decays. The components for the cryostat arrived from

factories in Russia, Italy, and Austria and were assembled and tested at CERN. The inner readout structure

with its support structure which is machined to an accuracy of better than 50m over Im and its

26 000 ribbons was assembled. The electronics for the calorimeter also progressed steadily. A prototype

readout board containing custom-designed integrated circuits was tested successfully in a beam. The

development of the components for the second-level neutral trigger and for the pipelined readout of the

remaining detectors was completed and the module production is under way.

Atomic and Nuclear Physics

NA43

The aim of experiment NA43 (Aarhus, CERN, Florence, Johannesburg, Strasbourg, Turin, Yerevan) is the

investigation of hard QED processes when high-energy electrons, positrons, and photons traverse single

crystals.

When multi-GeV electrons and positrons penetrate single crystals along axial/planar directions dramatic

effects appear. The reason is that cross-sections are governed by the electrical field in the rest frame of the

projectile particle. This field is proportional to the Lorentz factor y of the projectile which attains values of


10°-10° for electrons in the 100 GeV region. Resulting crystalline fields reach 10!7 V/cm as seen by the

particle. Such high fields cannot be produced in the laboratory, and crystals therefore become unique tools for

investigating strong field effects.

In 1995 several important changes were made to the experiment (Fig. NA43-1). A pair spectrometer,

involving a 0.7 Tm dipole magnet and two drift chambers, was installed. This now allows us to measure single

photon energies. Another drift chamber was installed in conjunction with our big 4.5 Tm sweeping magnet so

as to be able to tag on the radiated energy (often multiphotons). Finally a new cryogenic vacuum chamber was

installed. This is intended to be used for the study of electron-positron pair production in cooled crystals

where thermal vibrations should affect the photon conversion probability much less than at room temperature

(Fig. NA43-2).

Vac. Chamber I Vac. Chamber II with crystal with crystal

on goniometer on goniometer

DC1 DC2 DC4 Sc6 DC5 DC6 , E.M. Calorimeter e

Beam

Y

| Sc3 Vac. tube

BEAM DUMP

l ' ' 4

=0 40m 61m 65m 75m 77m 8im

Fig. NA43-1: The NA43 experimental set-up in 1995. DC = Drift Chamber, Sc =

Scintillation counter, B = Bending magnet. Vacuum Chamber II may be cooled to

liquid nitrogen temperatures. Both crystals are mounted on high-precision

goniometers (+2 Urad).

COOLING IN 0.6 MM SILICON CRYSTAL

150 GeV electrons incident

| O,, wrt crystal axis: 45 - 55 urad

| 0.012 hi — —0— 3<AE,g < 25 GeV

f I 1 57 < AELG < WO GeV

Counts

per

urad

oO S ©

80 = Oyu- On [nrad]

Fig. NA43-2: Example of radiative cooling. It is seen that electrons radiating

between 57 and 90 GeV on average experience cooling corresponding to 10 urad

focusing with respect to the direction of the crystal axis.


During three weeks in August 1995 we recorded 40 x 10° triggers. Three sets of data were taken:

1. Photon conversion probabilities in cooled W and Icrystals.

2. Photon initiated showering in a thick 25 mm Ge crystal.

3. Electron and positron radiation in thin (0.2, 0.6 and 1.5 mm) W, Si and C (diamond) crystals.

NAS54

The NA54 experiment (Munich TU, San Diego, PSI Villigen) studies the in situ production of cosmogenic

nuclides, which is important in many geophysical applications such as the determination of erosion rates; in

the determination of background in all low-level detection experiments such as cryogenic dark matter

detectors made of sapphire (AlyO3); or in geochemical experiments such as the geochemical solar neutrino

experiment 20ST)(e,v.)- Pb. The main in situ production mechanism of cosmogenic radionuclides are

spallation reactions and reactions induced by stopped and captured negative muons. Fast-muon-induced

reactions are the dominant contribution in depths greater than 100 g cm? in the lithosphere. The production

rate due to fast muons can be characterized by one effective cross-section and the energy dependence.

For the determination of effective cross-sections, a set of targets was irradiated with 190 GeV muons at the

high-energy muon beam M2. The secondary particle shower was obtained by a concrete block of a length of

3 m. The following targets were irradiated to produce the listed radionuclides: SiO, (2 targets) for Be, 14c

and ?eA1; CaCO; for 36C1; Fe for ”’Mn; S for AI; Al,O; for 26 Al and TI for ?°°Pb. For the determination of

the fluences at the targets, the lateral activation profile was measured using 35Fe and Ni monitor disks. The

measurement of the produced cosmogenic radionuclides with accelerator mass spectrometry is in progress.

Light and Heavy Quark Spectroscopy

WwA89

The WA89 experiment (Bristol, CERN, Genoa, ISN Grenoble, Heidelberg MPI, Heidelberg, Mainz,

Lebedev Moscow, Iowa, Rutgers) exploits the large hyperon fluxes available in the charged hyperon beam

installed in the West Hall at the Omega facility. A &” beam of about 330 GeV/c is used to produce charmed

strange baryons for which we measure lifetimes, branching ratios, production cross-sections, etc. The lowest

symmetric states are expected to decay radiatively to the ground (antisymmetric) states and are searched for by

using a lead glass calorimeter. The same data should also provide an important sample of the exotic U(3100)

states observed in the previous CERN SPS hyperon beam experiment WA62 and BIS-2, if these states exist.

The postulated double strange dibaryon H (uuddss) and the pentaquark P (Csuud,csudd) are also being

searched for.

The apparatus is built around the existing Omega magnetic spectrometer using a new set of high-resolution

silicon microstrip counters for the detection of the charm decay vertices and an additional set of drift chambers

and MWPCs for the detection of A decays. A set of transition radiation detectors is used for suppression of

beam pions. The upgraded wide angle RICH provides n/K/p separation up to 100 and 130 GeV/c, respectively.


Electrons and photons are detected in a lead glass calorimeter consisting of 650 blocks. Since 1993 we also

have included a hadronic calorimeter of the ‘spaghetti’ type together with a scintillating tile hodoscope to

detect final-state neutrons. The information of the TRD and the hadronic calorimeter are included in the

trigger of the experiment.

Data with full particle identification were taken in three periods of two months in 1991, 1993 and 1994.

The beam provides fluxes of up to 1.6 x 10° I /spill, with a n/&” ratio of 2-2.5 at the experimental target. A

large sample of about 600 million triggers obtained form &” interactions in C/Cu and silicon targets was

recorded and is being analysed. We have obtained signals for the known charmed mesons and charmed strange

baryons using a well reconstructed secondary vertex and particle identification. At present the analysis is

based on only part of the existing data set and a statistical improvement by about a factor 2-3 is expected.

We have measured the lifetime of the doubly strange charmed baryon (ssc) obtaining the result:

55 +12 (stat.) +18 (syst.) fs. This makes the (ssc) baryon the weakly decaying particle with the shortest

lifetime observed so far. In addition, we have measured the polarization of hyperons produced by a hyperon

beam.

WA91

The WA91 experiment (Annecy, Athens, Bari, Birmingham, CERN, Dubna JINR, IISN Belgium, Protvino

IHEP, Tsukuba KEK) searches for non-qq mesons produced in the central region in the reaction

pp > Pr x p, at 450 GeV/c using the CERN Omega Spectrometer. The data-taking stage of the experiment

was concluded in 1994 and analysis is in progress. An analysis of the n’n and r’n n'n mass spectra shows

that the enhancements observed in the 1.5 GeV mass region could be interpreted as being due to an

interference effect between the fy(1365) and fy(1520) previously observed by the Crystal Barrel Collaboration.

The ©/f,(1720), which is still an interesting non-qq candidate, is observed in the K’K” mass spectra and a

spin analysis is in progress to determine its quantum numbers.

WA102

Experiment WA102 (Annecy, Athens, Bergen, Birmingham, CERN, Dubna JINR, IISN Belgium, Los

Alamos LANL, Manchester, Oslo, Protvino IHEP, Tsukuba KEK) searches for non-qgq mesons produced in

the central region in the reaction pp > Pr x p, at 450 GeV/c using the CERN Omega Spectrometer and

GAMS-4000. This is a continuation of the WA76, WA91 and NA12/2 experiments which performed a

dedicated search for non- qq mesons in centrally produced exclusive events.

The aim of experiment WA102 is to make a more complete study of the mass region from 1.2 to 2.5 GeV

using the ‘gluon-rich’ production mechanism (DPE) and the charged particle reconstruction of the Omega

Spectrometer combined with the multiphoton detection of GAMS-4000.

The experiment had a very successful first data-taking run of 100 days in 1995 and collected 200 million

events which are now being processed through the event reconstruction programs. 1996 will see the closure of

the Omega Spectrometer and hence the last run of the experiment. For the 1996 run the set-up has been

modified by the addition of a threshold Cherenkov detector to allow more statistics to be gathered on the K*K”

final state.


Heavy-Ion Experiments

NA44

The focusing spectrometer experiment NA44 is a collaboration of Brookhaven, CERN, Columbia,

Copenhagen, Hiroshima, Los Alamos, Lund, Nantes, Ohio State, Texas A&M, Vienna, and Zagreb. The main

physics aims are the identification and precision measurement of a few particles in pp (p-Be), p-A and A-A

collisions around mid-rapidity. This is achieved by a set of dipole and superconducting quadrupole magnets

and a spectrometer arm including sets of tracking and particle identification devices stretching over more than

20. m.

1994 was dominated by the preparation for the first Pb beams at CERN. First results from the very

successful run in late 1994 were presented at the Quark Matter conference in January 1995.

During 1995 NA44 underwent a major upgrade to facilitate the operation and to further increase the data-

rate and quality. Until then it was not possible to use the uranium calorimeter, and the newly installed

hodoscope (H4) in front of it, at the large pr setting. In a combined effort with the SL Division the

experimental area of NA44 was enlarged and movable platforms for the calorimeter/hodoscope and the rest of

the spectrometer arm were installed. With this set-up it is now possible to move the spectrometer several times

faster and more reliably than before. A new trigger scintillator was developed to cope better with the beam-

related background. The data-acquisition was changed to the CASCADE/OSCAR system in collaboration

with the ECP Division. Together with an improved shielding which enabled us to run at higher beam rates, we

were able to improve, e.g., the statistics on the single particle measurements by more than a factor of 3.

The 450 GeV/c proton runs during the year were mainly used to test the new detectors and the DAQ

system, followed by a successful Pb beam period. In Fig. NA44-1 examples of inverse slopes for pions, kaons

and protons are shown for different symmetric systems. The slopes are increasing with particle mass

indicating an expanding system. The size of the system is studied by two-particle interferometry, Fig. NA44-2

summarizing results for kaons and pions for different systems. The radius parameter is increasing for heavier

systems and always larger than the projectile size.

3 03[|, | - ®© "| NA44 preliminary

o e: NA44 Pb+Pb » 0.25 | r

g Pa = „" NA44 S+S

02} a |

Fe

0.15 ® |

ko . . | A: ISR p+p

Mr m KK mp 1

0 0.5 1

mass (GeV)

Fig. NA44-1: Inverse slope parameters for pions, kaons and protons from p-p,

$-S and Pb-Pb collisions.


6 r R, v v v F A |

m No > ® Nrs

nr k 4 K n;

E22} © ' high pr

0 + t 4 }

1F -

| A u =

05, n u u -

0 1 L k 1

pPb SPb pPb pPb SPb PbPb

Collision System

Fig. NA44-2: Summary of radius parameters from 3-dimensional fits to the two-

particle correlation function for pions and kaons.

In 1996 NA44 plans to further increase the sample on kaon pairs for a larger transverse momentum range

and complete the data set on rare particles such as deuterons and anti-deuterons.

NA45

The NA45/CERES experiment (Brookhaven, CERN, Dubna, Heidelberg, Milan and Rehovot) is dedicated

to the measurement of electron-positron pairs and photons produced in hadron and nuclear collisions at SPS

energies. Its main goal is to study systematically the pair continuum in the mass region from 100 MeV/c? to

- 2 GeV/c? and the vector mesons p, @, and 6. The spectrometer covers the mid-rapidity region 2.1<n<2.7

with 2rt azimuthal symmetry and with a broad range of Pyerp-

CERES has completed a first round of experiments including the measurement of low-mass e*e” pairs in

p-Be and p-Au at 450 GeV/c and S-Au collisions at 200 GeV/nucleon. The e*e” spectra measured in the

proton-induced interactions are very well explained, both in shape and absolute magnitude, by electron pairs

from the known hadronic sources. On the other hand, the S-Au mass spectrum shows a different shape and a

strong enhancement in the mass region 0.2<m< 1.5 GeV/c? of a factor of 5.0+ 0.8 tat) #2(sys) Over the

hadronic sources. The onset of the excess, starting at a mass of - 2 m„, together with a possible quadratic

dependence on the event multiplicity, suggest the opening of the two-pion annihilation channel n'n — e*e”

atm=2m,.

CERES has started a second round of measurements using the Pb beam. In order to cope with the high

multiplicities of central Pb-Pb collisions the spectrometer has been upgraded by adding new detectors to the

basic double-RICH spectrometer: two silicon radial-drift chambers (instead of one in the original design) of an

improved design, located close to the target, and a multiwire proportional chamber with pad readout, behind

the spectrometer. They provide tracking both before and after the magnetic field, thereby helping the pattern

recognition of the two RICH detectors. Other essential elements of the upgrade are: (i) anew data-acquisition


system with a rate capability improved by one order of magnitude compared to the system previously used and

(ii) a new first-level trigger system.

The whole upgrade programme was implemented for the Pb run which took place in Nov.-Dec. 1995. A

total of 20 million events on Pb-Au collisions was collected and it is expected that the analysis of this data

sample will shed more light on the low-mass electron pair excess observed with the S beam.

NA49

The NA49 experiment (Univ. Athens, LBL Berkeley, Univ. Birmingham, KFKI Budapest, CERN, INP

Cracow, GSI Darmstadt, UC Davis, JINR Dubna, IKF Frankfurt, Freiburg, Marburg, MPI Munich, UCLA,

INS Warsaw, Warsaw, Seattle, RBI Zagreb) studies Pb-Pb collisions at the SPS. Its main objective is to

accomplish a charged particle exclusive registration of the complete hadronic final state. A multitude of

hadronic observables is investigated in nearly full phase space and in specific cases on an event-by-event basis.

In 1995 the second part of the detectors was constructed and the complete detector system successfully

brought into operation for the Pb run. The experimental set-up consists of two medium size TPCs (VTPC-1,

VTPC-2, 3 m? each) sitting inside two Vertex Magnets, two large size TPCs (MTPC-R, MTPC-L, 20 m? each) positioned downstream of the Vertex Magnets symmetrically to the beam, two TOF systems backing up the

MTPCs and a Veto calorimeter. The TPCs are built in a new low-mass technology using aluminized Mylar

strips strung around ceramic posts in the corner of the rectangular volume for the field cage and Mylar foils

glued to a fibreglass frame for the gas box. They are filled with the unconventional gas mixtures Ne/CO, 90/10

(VTPC-1,VTPC-2) and Ar/CO,/CH, 90/5/5 (MTPC-R, MTPC-L) and operated at low drift velocity (1.3 cm

per us for both VTPCs and 2.3 cm per us for both MTPCs) to allow for best spatial track resolution. Special

monitors were constructed in order to register the gas amplification to an accuracy better than 0.5% and the

drift velocity to 0.1%. The O, contamination in the TPCs is only 3-5 ppm.

The TPCs have pad readout and are equipped with a total of 182 000 electronics channels, the

amplification, shaping and digitization being performed on the detector. The digitized data are multiplexed and

sent to the VME-based receiver boards of the DAQ via optical fibres. An average fault rate of < 10* was

achieved. The noise could be considerably reduced to a sigma pedestal of about two channels.

The second part of the TOF system was constructed and successfully brought into operation. It comprises a

tile-wall of 600 scintillators and a grid-wall of 186 scintillators with two-end readout. A single channel time

resolution of 65-70 ns was achieved.

The complete DAQ system was installed and functioned successfully. The huge amount of TPC data is

read out in parallel via 240 DSP-96002 processors with 20 Mbytes of memory each, allowing for

multibuffering of events and a raw data compression of about 90%. During the six weeks of data taking

1.3 million events were recorded with a Sony DIR-1000M tape drive writing with 16 Mbytes/s on 100 Gbyte

cartridges. This corresponds to 10 Tbytes of data. The maximum event rate was 15-20 events per spill.

DST production started on CORE in the CERN computer centre using 8 SP2 and 20 HP-K200 processors.

By staging the raw data on a 2.4 Tbyte Sony DMS 24 tape robot, 5000 events/per day can be processed.


The analysis of the 1994 data is still in progress, but first results indicate a high energy density in the

primordial interaction volume of ca. 2.5-3.0 GeV/fm?, which is accumulated by a high degree of nuclear

matter stopping power. It results in a total c.m. transverse energy of more than 1 TeV in central collisions

which is carried by about 2100 created hadrons and about 400 participating baryons. The high store of

transverse energy is reflected in mean pr values for pions and baryons which are higher by about 80 and

200 MeV/c, respectively, than those found in p+p collisions at similar energies. This is illustrated in

Fig. NA49-1 by the transverse mass distribution of participant protons near mid-rapidity (mid = 2-9). While

the exponential fits describe the data very well, the inferred inverse slope temperatures of 280 and 260 MeV in

two adjacent rapidity bins exceed, by far, the Hagedorn limit of 160 MeV for a thermal hadron gas. An

alternative model could be hydrodynamic expansion of the densely packed hadrons, in which thermal energy

coexists with compression and/or collective flow energy. The first glance at two-pion correlations points

towards such an expansion scenario. Figure NA49-2 shows the results of a systematic analysis of the

longitudinal and transverse projections of the correlation which yields effective source sizes. These parameters

must decrease with the mean pair-momentum kp like kr"? if collective expansion characterizes the hadron

transverse and/or longitudinal motion. Parametrizing the data by kr“ shows that central Pb+Pb collisions

may indeed closely resemble the hydrodynamic picture, implying that the hadronic final state ‘remembers’ the

condition’s prevailing hadronization, i.e. close to the hypothetical phase transition.

Positives - Negatives = part - Protons Pb+Pb central NA49 Preliminary

zZ 102 E T T T | | T 2] L I I t I I I _

: E ; gE ı} 3<y<35 35<y<40 E T = 280 +30 MeV T=260+20MeV -

>= 10 E E 3 o r z

1 E + 3E

1 | | | ı ı] 4 l

0 0.4 0.8 1.2 0 0.4 0.8 1.2

M-my(GeV) m -mp(GeV)

Fig. NA49-1: mr distribution of participating protons for two adjacent rapidity

bins in central Pb+Pb collisions at 160 GeV/nucleon. Exponential inverse slopes

are 280 and 260 MeV, respectivel,.

0.8 FH I

076 trans. 5 long.

0.6 > =

0.5 > ua u nm m m a mn m m m m m m = sum onTdeoosoboou6beo me 4

3 F n 0.4 &- >

03 E E

022 b t E

01 2 3 0 04 | 4

2 2 a2 53 Zinn dh

Fig. NA49-2: Systematics of the flow parameter a obtained for pair-momentum

dependence of source radii in central S and Pb induced collisions.


NAS50

The NAS50 Collaboration (Annecy, IFA Bucharest, Cagliari, CERN, Clermont-Ferrand, LIP Lisbon, Lyon,

INR Moscow, Orsay, Palaiseau, Strasbourg, Turin) studies dimuons produced in Pb-Pb collisions, with the

aim of completing the physics covered with 160 and ??S beams by the NA38 Collaboration, the keywords

being J/ıy and w’ suppression, y enhancement, and an excess (over expectation from extrapolating p-U data)

around 1.5 GeV/c?.

A breakthrough on the theoretical side occurred in late 1995. Taking advantage of the computability of the

hard processes involved, D. Kharzeev and H. Satz were able to establish that all the available data on J/y and

W’ produced in collisions from p-p to S-U are explained by absorption in a hadron gas, and the formation of a

Quark-Gluon Plasma by 325 beams can be excluded.

Regarding the experiment, the core of the detector is still the NA10 Dimuon spectrometer, with part of the

hodoscopes remade. The wanted muons now traverse a dense BeO absorber. This and the use of a higher

magnetic field have improved the mass resolution at the J/y from 140 to 105 MeV/c?. Most new beam and

target region detectors are complete and work well. The use of Cherenkov radiation in quartz has been

generalized, with very good results. The Zero Degree Calorimeter (ZDC) has performed very satisfactorily,

and gives the new impact-parameter measurement. Slight radiation damage was measured in its quartz fibres,

after exposure to 4 x 107 Pb ions per burst over several weeks. The multiplicity detector is made of two planes

of Si pads. While it is not complete yet, its performance is improving.

The new scheme of spreading the beam over the full length of the SPS vacuum chamber led to a doubling

of the effective duty cycle, with corresponding improvement in the luminosity of the experiment.

Some 50 million triggers were recorded overall. Technical runs included a test of the ‘y’ set-up (minimal

absorber, low field), for low mass physics, which needs some improvement; runs without the first absorber

part, in order to evaluate the background subtraction procedure; and calibrations of the two calorimeters. The

main physics run was done with the ‘J/y’ set-up (high field, and an iron shield terminating the hadron

absorber). Results are intriguing: both J/y and w’ are produced less abundantly than expected from the

‘Hadron Gas’ extrapolation from p-A and S-U data.

NAS52

The NA52 experiment (Annecy, Bern, CERN, Helsinki, Stockholm, Strasbourg) aims to detect strangelets

—small drops of strange quark matter— which might result from the extreme energy and baryon densities

attained in Pb-Pb collisions at a beam momentum of 158 GeV/c per nucleon. The experiment uses the H6

beam line as a spectrometer equipped with wire chambers, a time of flight measurement over a path of 524 m,

and a hadronic calorimeter at the end of the set-up.

During the 20 day run in the autumn of 1994 we accumulated data of 1.8 x 10!? Pb ions on our Pb targets.

The average beam intensity was 5 x 10’ ions per spill for the NA52 experiment. We were running mainly with

a 40 mm target at spectrometer rigidities of +/-100 GeV/c and -200 GeV/c and with a 16 mm target at

+200 GeV/c. After looking at more than 101! Pb-Pb interactions per setting we did not observe any heavy


object with a mass-to-charge ratio m/IZI between 5 and 60 GeV/c? at a rigidity p/Z = +/-100 GeV/c and

between 8 and 120 GeV/c? at /Z = +/-200 GeVic.

These data allow one to calculate the upper limits for the production of strangelets shown in Fig. NA52-1.

The resulting values strongly depend on the production model. Here we assume a differential production

cross-section factorizing in a Gaussian rapidity distribution with a width of 0.5 and an exponential transverse

momentum distribution with a mean of O.1 (mGeV)! 2 The sensitivity is defined as S(m) = 1/ (N. x f(m));

Nint 15 the number of interactions, f(m) is the detection probability for a strangelet in the beam line.

During the Pb-ion run in 1995 the statistics for the strangelet search at a rigidity of -200 GeV/c has been

improved by about one order of magnitude. This was mainly due to a better spill structure and a very efficient

running of the accelerator. The analysis of the 1995 data is in progress.

‚os. Pr: 0.1\ m GeV 100 Gevie, (1.1.10'° int E "oy=05 +100 GeV/c (2.1 10" int) 1Zi=1 Y Pat

106 L.

N

sens

itiv

ity

S{m)

[p

er in

tera

ctio

n]

7 / X SE / +200 GeV/c (1.1 1011 int)

-200 GeV/c (1.2 1011 int)

/ L

10% \, /

OL

109 1 au FREE ER FREIEBEN 0 [0

0 20 40 60 80 100 120

m [GeV/c2]

Fig. NAS2-I: Upper limit for the production probability of strangelets in Pb-Pb

collisions, based on the data taken in Nov./Dec. 1994.

WA9T7

The WA97 experiment (Athens, Bari, Bergen, Birmingham, CERN, Genoa, Kosice, Legnaro, Oslo, Padua,

Paris College de France, Prague, Rome, Salerno, Serpukhov, Strasbourg) studies the production of

strange baryons and antibaryons in high-energy nucleus-nucleus interactions, using Pb and proton beams at

160 GeV/c per nucleon. It searches for a Quark-Gluon Plasma signature by studying the increase of strange

baryon and antibaryon production with respect to ‘normal’ hadronic interactions.

The experiment covers the two central rapidity units for transverse momenta 2 few hundred MeV/c. It

consists of the Omega spectrometer equipped with a) trigger counters, b) two stations of microstrip

multiplicity detectors, c) a telescope made of 10 planes of Si microstrip detectors (10 000 channels), 7 planes

of Si pixel detectors (500 000 channels) and 1 plane of Si pad detector (1000 channels), d) a set of 3 gas pad

chambers as lever arm detectors (9000 channels).


In the 1994 runs, K,, A, &", and (27 signals were obtained from 12 million Pb-+Pb interactions. Preliminary

results were presented at Moriond (1995), at the Multiparticle Dynamics Conference (1995) in Stara Lesna

and to the SPSLC (1996). In 1995, we had both a p+Pb and a Pb+Pb run collecting about 290 and 120 million

triggers, respectively. The whole set-up worked rather smoothly and the analysis has started.

A unique characteristic of the experiment is the use of silicon pixel detectors developed in collaboration

with the CERN RD19 Project. Such detectors are well-suited for tracking in a high multiplicity environment

since they are capable of determining the space points on a track directly, i.e. with a two-dimensional readout.

We used seven planes of such detectors each having 72 000 sensor elements (500 x 75 mm) and covering an

area 0f5x 5 cm?. All the planes worked satisfactorily.

WA98

The WA98 experiment (Bhubaneswar IOP, Calcutta VECC, Chandigarh, Darmstadt GSI, Dubna JINR,

Geneva, Groningen, Jaipur, Jammu, Lund, Moscow RRC, MIT, Münster, Nantes SUBATECH, Oak Ridge,

Rez NPI, Tennessee, Utrecht, Warsaw) studies hadron and photon production in Pb+Pb collisions with the

goal of producing hot hadronic matter over a large volume and searching for signatures of a transition to a

Quark-Gluon Plasma (QGP). A special emphasis of the experiment is on broad global characterization of the

reaction to identify and select unusual event features or event classes. The space-time evolution of the reaction

volume is studied via Bose-Einstein correlations of identified charged hadrons. The thermal history of the

system is investigated by measurement of direct photons.

The WA98 experiment consists of a highly segmented lead glass photon Detector Array (LEDA) of

10 000 modules placed at a distance of 21.5 m from the target. The momentum spectra of neutral pions and

etas are reconstructed from their two-photon decay over the rapidity region of 2.1<y<3. Careful

determination of the photon yield from neutral pions and etas allows one to search for excess direct thermal

photons. The photon multiplicity measurement is extended over the range 2.8<y<4.] with a 7x4m

preshower Photon Multiplicity Detector (PMD). Negative charged particle tracking with time-of-flight

measurement allows momentum measurement of identified pions, kaons, and anti-protons in the range

2<y<3. The tracking is achieved using a set of six 1.6x 1.2 m? multi-step avalanche counters with image

intensified CCD camera readout located downstream of the Goliath magnet. A positive tracking arm using two

avalanche counters and two streamer tube planes all with pad readout and with time-of-fight measurement

will be installed in 1996. The tracking arms provide charge-particle momentum spectra and two-particle

correlations. Used in combination they will allow us to study the phi-meson via its two-kaon decay branch.

Total charged particle multiplicity is measured in the range 2.0 < y < 3.4 in the Silicon Drift Detector (SDD)

and in the range 24<y<3.8 in the Silicon Pad Multiplicity Detector (SPMD). Together with the PMD

detector, the charged particle multiplicity detectors allow us to study the N (photon) / N(charged) ratio on an

event-by-event basis to search for non-statistical fluctuations reflecting fluctuations in the ratio of neutral to

charged pions. Such fluctuations are a predicted signature of formation of a disoriented chiral condensate in

the transition from QGP matter to hadronic matter. Finally, for centrality selection, the transverse energy and

forward energy are measured in the MIRAC and Zero Degree Calorimeters (ZDC), respectively.

The autumn 1995 run period was very successful with more than 15 million Pb+Pb events taken and all

detectors in good operation: Figs. WA98-1 and WA98-2 show results from a preliminary analysis of the 1995

Pb+Pb data. Figure WA98-1 gives an overview of the capabilities for measurement of global variables. In this


figure the forward energy measured in the ZDC, the charged multiplicity measured in the SPMD, and the

photon multiplicities measured in the PMD and LEDA are each plotted versus the transverse energy for

minimum-bias events. These global variables will be used for centrality selection as well as to search for

unusual event characteristics, such as might arise from a disoriented chiral condensate. Figure WA98-2 shows

the transverse momentum distribution of neutral pions for roughly the 10% most central and 10% most

peripheral collisions from less than 1% of the 1995 data sample. Besides the obvious increased yield for

central collisions an increase in slope of about 10% is observed.

WA98 LEDA n? spectra (1995)

& +.

st | \

Z10s | + t U central

108 |

1077 peripheral r

„el H 10°} Pb+Pb 160 A GeV u

: acceptance corrected ' very preliminary

10-10 0 500 1000 1500 2000 2500 Pr (MeV/c)

Fig. WA98-1: Correlation of measured forward energy, charged particle multiplicity,

and photon multiplicities with transverse energy for minimum-bias Pb+Pb events.

WA98 Results Pb + Pb (1995 Run) Very Preliminary

40 „0

= >| Sn E30 Pe, 5 ia

257°, = soo} Lie e 201 3 ET u [ Do nn

5 157 5 S 400 7 A Fa 10 177 oO IR

u: "| 207 0 u ” 0 Be

1000 0 200 400 600 800 400. 200 400 600 800

2 | 2 30f

a er 3 30, = =

su ee Be S Er s 2007 Me 8400| .; 2 0 Q- BE Bau: itz

S 200 1: gs 1007 „ie

0r or — ı 0 200 400 600 800 0 200 400 600 800

Transverse Energy (GeV)

Fig. WA98-2: The transverse momentum distribution of neutral pions measured with the

lead glass array for central and peripheral Pb+Pb reactions.


For 1996, WA98 will complete installation of the charged-particle veto detector for the lead glass array and

install the second tracking arm for positive charges. In addition to the autumn lead run, proton reference data

will be taken in the spring.

EMUI1

The EMU11 Collaboration (SUNY Buffalo) investigates Pb-induced emulsion collisions at 160 A GeV to

explore a variety of important aspects related with hot and dense nuclear matter in order to extend our

knowledge of the nuclear equation of state. The advantage of using nuclear emulsion is that it acts

simultaneously as a target as well as a detector for all kinds of target and projectile related charged particles

emitted in nuclear collisions. So far, we have collected a minimum-bias sample of about 1300 events using

along-the-track scanning technique. Charges have been assigned to all the projectile fragments of charge Z2 2

that emerged in about 1000 interactions. Angular measurements on 337 events having at least four projectile

fragments with Z 22 have been completed and their pseudorapidity distributions are constructed. The results

are compared with our existing data of the Au beam at 10.6 A GeV obtained from the BNL AGS.

EMU12

EMU12 is a continuation of the EMUO1 experiment (Alma-Ata, Beijing, Bucharest, Chandigarh,

Changsha, Dubna, Jaipur, Jammu, Kosice, Linfen, Lund, Marburg, Moscow, St Petersburg, Seattle, Seoul,

Sydney, Tashkent, Wuhan, Yerevan) using nuclear emulsions as detector to study ultra-relativistic heavy-ion

interactions. The main aim of the experiment is to investigate the global aspects of multiparticle production

like the mass and energy dependence of charged particle multiplicities, angular distributions of charged

particles, and target and projectile break-up. The experiment, however, also focuses on local particle density

fluctuations.

Within the collaboration two complementary techniques are used, each with its own advantage. The

conventional technique with horizontally exposed stacks is predominantly used for obtaining minimum-bias

data, and for special studies of the target break-up. In order to gain maximal resolution in interactions of

extreme multiplicities, where many particles are produced in a narrow cone, the use of vertically exposed

emulsion chambers facilitates the measurements.

During the last year the groups within the collaboration have been occupied in measuring events from the

December 1994 lead-beam. In parallel, analysis work on the new data and data from previous runs at the SPS

and AGS has been going on. Among the different analysis projects we would like to mention studies of

rapidity densities in central Pb+Pb interactions, collective flow and reaction planes, non-statistical fluctuations

of particles produced in the central rapidity region, emission of helium fragments from the projectile, and

studies of the target break-up into slow, charged particles.

Figure EMU12-1 shows the squared transverse momentum distribution of helium fragments from the

projectile emitted in Pb+Pb interactions at 158 A GeV/c. Also shown in the figure is the same distribution

from Au+Au interactions at 11.6 A GeV/c. As can be seen the two distributions are in good agreement,

indicating that the mechanism responsible for projectile break-up into light fragments is energy independent.

The distribution can be parametrized as the sum of two independent momentum components of Gaussian

shape. The second component is indicated by the dashed line. This second component corresponds to an

extreme momentum transfer and no satisfactory explanation is readily available.


dN„e/dpr?

He particles %x Pb +Pbat 158 A GeV/c oO Au + Auat 11.6 A GeV/c

4 4, |

Dh 3 A

5 Pr (GeV/c)?

10

Fig. EMUIl2-1: Squared transverse momentum distribution of helium fragments

from the projectile in Pb+Pb interactions (stars) and Au+Au interactions (open

circles).

EMU13

The EMU13 Collaboration (Krakow, Louisiana, Minnesota, Moscow KLMM) exposed stacks of nuclear

emulsions and emulsion chambers with lead targets to a beam of lead ions of 158 GeV/n in order to study Pb

interactions with heavy components (Ag and Br nuclei) of the emulsion and Pb-Pb collisions. In

Fig. EMU13-1 the pseudorapidity distributions of all singly charged particles for Pb-Ag/Br and Pb-Pb

collisions are presented and compared to the Monte Carlo simulations. The shape of the measured

distributions agrees with the model calculations except for the very large pseudorapidity values, where the

data show spectator protons not accounted for in the model simulations. The highest multiplicity event

observed is the Pb-Pb collision in which 1729 + 100 secondary particles are produced. The charged particle

pseudorapidity density for this event is 410 yielding the energy density of 1.2 GeV/fm.

300 250F 2008 1/

N,‚dN/dn

1/N,‚dN/dn

Fig. EMU13-1: The pseudorapidity distribution for (a) Pb-Ag/Br and (b) Pb-Pb

interactions (solid lines) and for Monte Carlo simulated events (dotted lines).


The analysis of non-statistical fluctuations was performed for the sample of Pb-Ag/Br collisions by means

of factorial moments of the particle density distributions in phase space domains of varying sizes.

In Fig. EMU13-2 the fitted intermittency indices in pseudorapidity and in the azimuthal angle bins are plotted

as a function of the order of the moment, for the data and Monte Carlo simulations. The existence of

dynamical fluctuations was found in the azimuth, contrary to the model predictions. The intermittency indices

for Pb-Ag/Br collisions are found to be considerably larger than those expected from the extrapolation of

hadronic results to the same pseudorapidity densities, confirming the earlier observations, and indicating the

presence of collective phenomena in nuclear collisions.

(a)

ı | 1

-0.05 F -

L__ Lt l L

Bu 2 3 4 5 q

oa 0.1 IT 1. I 1.

(b) 0.05 F 4 =

+ v 0 26 © -— &

1.05: {

| il 1 l t

0 2 3 4 5 q

Fig. EMU13-2: Intermittency indices versus the order of the moments for the

Pb-Ag/Br data (full circles) and the Monte Carlo simulations (open circles) for

the analysis of (a) pseudorapidity and (b) azimuthal angle bins.

EMU15

The EMU15 Collaboration (Moscow Lebedev, St Petersburg PTI, Alma-Ata) investigates hadroproduction

process peculiarities in central Pb-Pb ion collisions at 160 A GeV on an event-by-event basis, searching in

particular for possible signals of the Quark-Gluon Plasma (QGP).

Primary experimental material on Pb-Pb central collisions was obtained with four emulsion magnetic

chambers irradiated by the Pb beam in the magnetic field of 1.8 T at the CERN SPS in December 1994. The

semiautomatic system ‘MICRON?’ including a microscope and block of automatics was modified specially for

this experiment, and a program packet for the treatment of particle traces in emulsion layers was elaborated.

Preliminary results of the data analysis show some peculiar patterns in several central collisions (e.g. ring-like

events, multiple narrow spikes in secondary particle pseudo-rapidity distributions, etc.). Data analysis is in

progress.


In parallel, theoretical investigations of the hydrodynamic expansion of the primary fireball, of

multiparticle correlations, and of the double phase transition between hadronic matter and QGP were

performed intended for future analysis of experimental data. Results were presented at several international

conferences.

EMU18

The EMU1S8 Collaboration (Bologna) exposed six stacks of nuclear track detectors in December 1994 to

207pp82+ jons of 160 GeV/nucleon at the CERN SPS. Each stack was made of CR39 and Lexan sheets placed

before and after a target. When passing through the stack the lead ions produce nuclear fragments with Z < 82.

The main purpose of the exposures was the calibration of the CR39 nuclear track detector used in a large-area

experimental search for magnetic monopoles at the Gran Sasso Laboratory (experiment MACRO). Different

targets were used in order to study also the fragmentation properties of lead nuclei (Fig. EMU18-1). The

exposures were carried out at normal incidence at a density of - 400 ions /cm?. The typical number of events

in a stack was - 1.5 x 10%, 5 times lower than what had been planned.

500 AT Te

450

400

350

300

250

200

150

T TTTeePeITTTen

DH

pIerTpereepTeeETeren

| Mi a

TerTeem

4 ı

4 l

TI

ı Tl

Ir

Pr

3 I

TI

ı Tr

Numb

er

of ev

ents

50 sh hans hass a horn hans hang hans han ls nn

0 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000

Area (pixel?)

Fig. EMU18-1: Number of nuclear fragments from the fragmentation of Pb ions

in copper; the horizontal scale is proportional to the charge Z of the nuclear

fragment.

The measurements for the calibrations of CR39 have been essentially completed. We compared the

response of CR39 etched in (a) NaOH 6N at 70°C and (b) NaOH 6N at 40°C, and (c) NaOH 8N at 80°C

(Fig. EMU18-2). The sensitivity of the detector decreases with decreasing etching temperature and decreasing

concentration of the solution; the highest charge resolution is for CR39 etched ın the conditions (b). The

lowest detected charge is Z=5 for CR39 etched as in (a) and (c) and Z=9 if etched as in (b). The results

indicate no relevant ageing effects for the CR39 made more than five years ago. The investigation of possible

fading effects for CR39 stored in the Gran Sasso Laboratory is in progress.

Because of the small number of collected events, additional runs at higher beam intensities are needed for

the determination with good accuracy of the fragmentation cross-sections of lead ions and to obtain limits on

fractionally charged nuclear fragments.


10 _ T 1 1 I T- ! T | T 1 T T T

°F m etch.Na0HaN, 0°C E [ |

77 e etch. NaOH 6N, 70 °C ! -

„® 4. etch. NaOH 6N, 40 °C „" e >| . ' o ” 5% a" | ® n m

8° . | 2. u

u © o.?° as = „oe. ° art u . . © oe ® : i A A WW,

® a 1 o_ L l N 20h & l L \ i L

102

REL (MeV cm? g"')

Fig. EMUI8-2: Calibration of the CR39 with nuclear fragments from the Pb

beam. Reduced etch rate p versus Restricted Energy Loss (REL) for different

etching conditions.

EMU19

The interactions of relativistic energy heavy ions with matter is an area of current studies. Solid-State

Track Detectors have been used extensively in the study of low-energy heavy-ion interactions. However, their

use for relativistic energy heavy ions has been somewhat limited. The knowledge of track formation

mechanisms by the ions at high energies is imperative for the analysis of interaction processes. To this end a

beam of 160 GeV/u Pb ions for the EMU19 experiment (Islamabad) was allowed to interact with a stack of

CR39 plastic (Cj>3H1g07).

This stack was exposed perpendicularly to a beam of Pb ions. A few detectors from the stack were selected

to observe the tracks of 160 GeV/u Pb ions. The detectors were etched in a6N NaOH solution at (70 +1) °C

in small etching steps. The etch induction time was determined to be about three hours. Further etching of the

circular tracks showed a linear variation of track diameters with etching time (Fig. EMU19-1). The slope of

this line was found to be 2.3 um/h, whereas the intercept was found to be 5.7 um in the etching interval of

3hst<s20h.

To probe the mechanism of track formation, post-exposure annealing of tracks formed in the CR39 track

detector was carried out. Several pieces from the stack of CR39 track detectors were annealed at various

temperatures ranging from 70°C to 200°C. A peak in the track diameter was observed around 180°C

(Fig. EMU19-2). Since the parameter V= V,/V, (V, is the etching rate along track and V, is the general etching

rate of CR39) was found to be constant with etching time, track diameters were, therefore, proportional to V,.

Our previous results with fission fragments from 252Cf and alpha particles from 240pu also show a peak in the

diameter around 180°C. From this, we conclude that track annealing behaviour of 160 GeV/u Pb ions is

similar to low-energy fission fragments and alpha particles from ?*"Pu.


DD

&

160 GeV/u Pb-Ions

Detector: CR-39 Etchant: 6N NaON

[Etching Temperature: (70 +1) °C

DD

©

rn >

T

TRACK

DIAMETER (m

) nD

m

20 r

18 +

16 l L l i l L l l L L l

2 4 6 8 10 12

ETCHING TIME (hour)

Fig. EMUI9-I: Variation of track diameter versus etching time.

26

94 Beam Energy = 160 GeV/u Pb + CR-39 [

- ETCHING time (15 hour) __ =z21 , Ss 1 5 20

& sl er >

iu 167 ETCHING z 14L time a a n (12 hour)

© 12 -

0 _ | —l L_ | |

0 50 100 150 180 20

TEMPERATURE (°C) >

Fig. EMU19-2: A plot of annealing temperature versus track diameter for

160 GeV/u Pb ions.

LEAR Programme

Hadron Spectroscopy and NN Interaction

PS185 and PS185/2

Experiment PS185 (Carnegie-Mellon, CERN, Erlangen-Nürnberg, Freiburg, Jülich, LAMPF, Uppsala,

Urbana-Champaign, Vienna) studies the exclusive production of hyperon-antihyperon pairs in proton-

antiproton annihilations in flight at LEAR. Detailed information on the dynamics of strange-antistrange

quark-pair creation has been obtained by precision measurements of total and differential cross-sections, as

well as final-state polarization and spin correlations. The reaction channels investigated from the respective


thresholds up to 2 GeV/c beam momentum include neutral hyperons, pp > ALP +c.c., as well as charged

ones, pp>Ltrtt, and pp 2-2-. At energies above 1817 MeV/c the reaction Bp—AAn® is

accessible. The experimental method also allows the study of antiproton-proton annihilation into strange,

neutral mesons pp— K,K,. Many results have been obtained, and the most recent data are still being

analysed. The experiment PS185/2 is essentially a continuation of PS185 and studies the Bp— AA reaction

to resolve a possible structure about 1 MeV above the threshold at 1435 MeV/c antiproton beam momentum.

The data taken in 1994 are currently being analysed.

The cross-sections for Pp>AA and pp>ALP +c.c. are both forward peaking. New data for the

reaction Pp—XX at 1.945 and 1.992 GeV/c increase the statistics in these channels by an order of

magnitude. The cross-section for pp — ZtIt is strongly forward peaking as well, while this is much less

pronounced in the pp > Z-2- reaction. This can be understood as an indication for a strong two (or more)

meson exchange contribution to the baryon-antibaryon production in the latter channel.

The reaction pp—AA exhibits large final-state polarization. They are positive at low momentum

transfer t and change sign at a fixed reduced momentum transfer t”= (t— tin) Up to beam momenta around

1700 MeV/c. For higher momenta the value of t” at the zero crossing of the polarization decreases. The A

polarization in pp— AZ +c.c. indicates an oscillatory structure as well; however, the errors prevent any

definitive conclusions. The spin S = 0 production probability (‘spin-singlet fraction’) determined from spin-

correlation coefficients forthe AA final state, was found to be consistent with zero over the full energy range.

This striking result implies that the AA pairs are always produced with their spins aligned. A natural

explanation for this would be given by intrinsic strangeness in the proton, as suggested by models inspired by

recent data from deep inelastic lepton scattering. The singlet fraction shows a non-zero value for the

AZ° +c.c. final state.

The sample of 165.000 pp—>AA events was used to extract the asymmetry parameter

A= (a+&)/(@-&) = 0.006 +0.015. This value is consistent with CP-conservation, but it is still some

orders of magnitude away from sensitivity to model predictions.

PS197

The PS197/Crystal Barrel Collaboration (LBL Berkeley, Bochum, Bonn, Budapest, Carnegie-Mellon,

CERN, Evanston NWU, Hamburg, Karlsruhe, QMWC London, UC Los Angeles, Munich, Paris VII,

Pittsburgh CMU, RAL-Rutherford, Strasbourg, Zurich) uses a large-acceptance (- 4 ) magnetic spectrometer

and electromagnetic calorimeter (1380 Csl crystals) for the kinematically complete reconstruction of almost

all antiproton-proton and antiproton-neutron annihilations at rest and in flight up to momenta of 2 GeV/c. The

physics goal is to identify all light mesons in the mass range from 0.14 to 2.3 GeV, to determine their quantum

numbers and decay properties, and to study the annihilation dynamics. The main interest is to find the

glueballs and hybrids predicted in the framework of Quantum Chromodynamics.

The main upgrade in the past year was the replacement of two PWCs by a cylindrical silicon vertex

detector with 1920 strips, with the objective of improving the momentum resolution of charged tracks, the

vertex resolution and the trigger efficiency for final states containing K-short particles.


The most important result is the confirmation of the fg(1500), found earlier by the Crystal Barrel

Collaboration, in various other decay modes, and the observation of the decay of a pseudoscalar E/ı into nn.

A wide scope of further physics results has been published: observation of radiative antiproton-proton

annihilation into a ® meson; the first observation of Pontecorvo reactions with a recoiling neutron; first

observation of the production of nucleon resonances in antiproton annihilation in liquid deuterium; the results

of a search for a new light gauge boson in decays of m, n, and n’; and the study of n decays into three pions.

PS201

The PS201/OBELIX experiment (Bologna, Brescia, Cagliari, CERN, Dubna, Frascati, Legnaro, Padua,

Pavia, Trieste, Turin, Polytech. Turin, Udine) is studying p and n annihilations within a programme of

meson spectroscopy, of NN annihilation dynamics, and of nuclear and atomic physics. The main goal in the

meson spectroscopy research is the discovery of exotic mesons allowed by QCD, like multiquark states,

hybrids, and glueballs. The research strategy of OBELIX is to start from initial states of definite isospin (np,

pn) and angular momentum (the S and P wave contributions to the pp annihilation at rest can be changed by

varying the target density), to look for exclusive reactions and to select specific final states by an extended use

of triggers (multiplicity, topology, kaons, X-rays, photons from 1).

In 1995, despite several problems in the PS complex (three weeks of beam lost for the experiment) over

10° events were written on tape (DAQ up to 70 Hz). This was done exploiting the full spectrometer and its

flexibility.

Several significant physics results were obtained during 1995 on annihilation dynamics and meson

spectroscopy as well as on nuclear and atomic physics. To quote a few of them:

—- Good evidence, in the E/ı region, for two pseudoscalar resonances (1416 +2 and 1460 + 10 MeV/c?),

coming from a Is pp state, was found with the LHj target. This result is fully confirmed by the data

taken with a GH; target at NTP. The possible existence of a third, axial vector resonance needs further

investigation.

— The analysis of the exclusive ap — nn’ (4C fit) requires both the fy(1500) and the f,(1520). The

pp > nn (analysis almost completed) seems to confirm this result.

— The OZI rule has been found strongly violated in the Pontecorvo reaction pd > ®n, compared with

pd > on, and the data agree with a suggested dependence on momentum transfer.

— Ten new annihilation frequencies were measured (in some cases, e.g. K,Kj, at different target

densities). In particular, the Pontecorvo process pd > AK? is clearly seen with a frequency as low as

5+2)x 107.

— The pp annihilation cross-section at very low B momentum (43-70 MeV/c, almost pure S wave) is

found to be in good agreement with the CCM model with Coulomb interaction.

PS202

The PS202/Jetset Collaboration (Bari, CERN, Erlangen, Freiburg, Genoa, KFA Jülich, Oslo, Uppsala,

Urbana-Champaign) uses an internal hydrogen jet target in the LEAR storage ring, surrounded by a compact


non-magnetic detector, to study exclusive mesonic final states formed by antiproton-proton annihilation in-

flight. The experiment focuses on the B@ final state, which is expected to be suppressed according to the OZI

rule. Such suppression might be overcome by the presence of an intermediate resonance of a gluonic nature,

which makes this reaction of particular interest in the search for gluonic mesons.

During the data-taking phase, spanning 1991 to 1994, 700 million triggers were collected for the B&

reaction. The production of these data, a total of 1.5 Tbytes, was completed in 1995. The luminosity was

calculated, based on the measurement of the elastic scattering rate, to a relative precision of 2%, with an

absolute uncertainty of 15%. The identification of 4K* events among the dominant multi-pion component of

the 4-prong sample relied upon the ring-imaging Cherenkov counter (RICH), dE/dx information from the

silicon pad detector, and information from the trigger threshold-Cherenkov counters. The acceptance of this

procedure was determined via extensive Monte Carlo studies, based upon a sample of 20 million simulated

&@ events plus several important background channels, generated during 1995.

The results of this analysis reveal a®@® cross-section that reaches a maximum near the lower end of our

measurement range, and drops off rapidiy with increasing antiproton momentum or invariant mass. At the

peak, the cross-section exceeds the OZI expectation by over two orders of magnitude. During 1995, as a

further means of investigating the possible role of intermediate resonances, a procedure was developed to

analyse the angular distributions of the detected kaons in terms of the underlying partial waves. A preliminary

result from this study shows the dominance of J(PC) = 2(++) waves in the vicinity of the maximum in the

cross-section, accompanied by a sharp decrease to higher mass. The analysis of the full data sample will reveal

whether the 2(++) strength exhibits a classic Breit-Wigner shape.

Several other channels are being analysed in parallel with the P® one. A preliminary result for the Pw

channel was produced, confirming the large OZI violation in the ratio PP / Pa. In the K,K, channel a scan

was made for the &(2230) which has been seen in radiative J/y decays to both K,K, and pp, with results in

agreement with previous measurements. The successful reconstruction of all-neutral triggers was

demonstrated, which will allow the extension of this search to new final states such as nn.

Fundamental Symmetries: CP Violation

PS195

The CPLEAR experiment PS195 (Athens, Basel, Boston, CERN, Coimbra, Delft-TU, Fribourg, Ioannina,

Liverpool, Ljubljana, Marseille-CPPM, Orsay-CSNSM, PSI-Villigen, Saclay-CEA-DSM/DAPNIA,

Stockholm, Thessaloniki, ETH-Zürich) has been designed to investigate CP, T and CPT symmetries in the

neutral kaon system through the Ks-Kj, interference by measuring the decay rate asymmetries between K'

and K® for the three main decay modes. In contrast with the traditional Ks-Kı experiments, it compares the

decay of an initially pure K® into a final state with its CP conjugate process. The symmetrical and concurrent

production of particles and antiparticles in pp annihilation at LEAR, as well as the symmetric detection of

their decay product, has the considerable advantage of minimizing systematic errors.

In 1995, the experiment took data with a detector improved by the addition of a small proportional

chamber surrounding a high-pressure gas hydrogen target. The chamber formed part of the trigger resulting in

an improved signal-to-noise ratio (by a factor - 2.5) and a higher number of events recorded to tape. The total

number of KP, K0 events available for physics analysis up to and including 1995 is - 10°.


Neutral kaon decays into n’n provide a determination of n,_ with the best accuracy currently available

world-wide (Fig. PS195-1). The comparison of @,_ with the superweak phase serves as the most sensitive test

of CPT invariance. The additional information from the n*nn® and semileptonic decays [Im(n,_o) and Im(x)]

allows this CPT test to be performed in a precise manner. The group has achieved the best precision in the

measurement of the Ks-K;, mass difference (Fig. PS195-2). The experiment also provides the best limit on

the CP violation parameters for the K, > nn decay (Fig. PS195-3) and the best measurement of the CP-

conserving branching ratio for Ks > ann’ of about 4x 10°”.

Ay-{ı) f

06}

041

021

01 -02| -0.4

061 €

-08 |

Fig. PS195-1: KO, K decay to two charged pions. The asymmetry A, +, - asa nz

function of the decay time. The solid line is our best fit to the data collected until

mid 1995 with In,_! = [2.269 + 0.033 (stat.) £ 0.030 (syst.) & 0.011 ts] x 107

and p,_= [42.2 + 0.7 (stat.) + 0.5 (syst.) £ 0.8 Am].

> 0.8 u

E07N E o 0.6 A

05E am

pt

0.4 5 0.3} 0.2,

0.1

OF .

15

pr

1

. \e

A 1 ih ı 11 a Dil sıı Li 00 Ta

2 AA 6 8 10 12 1 16 18 20 Ur,

Fig. PS195-2: K, KP semileptonic decay. The asymmetry Ay:

A \ |R(X° > e*tnv)+R(K 4 e"ntv)|-[R(K® > entv)+R(K® >, e*z-v)|

amtT [R(K° > e*n"v)+ R(K° u e-z*v)|+|r(K® > ent v)+ RK > etn v)|

is plotted with our best fit value Am = [0.5269 + 0.0022(stat.) + 0.0005(syst.)] x 10!° hs.


0.25.

2 | "FE vo.

0.15 E ® Ä

of

0.05 F

Once L

} 0.05 @ Barminetal

0.1 y Metcalf et al

0.15 TA Zouetal

-02 | CPLEAR [

-0.25 STEEL EEREEUEEEE EEEERUEEEREEREERERRNHEG

0.25 0.2 -0.15 -0.1-0.065 0 005 01 0.15 02 0.25

Fig. PS195-3: A measurement of the CP violation parameter for K, > nn?

compared to previous measurements.

The experiment will take data in 1996 using a carbon regenerator in order to reduce the largest source of

systematic error in the determination of @,_.

Nuclear Physics with Antiprotons

PS208

The objective of the PS208 experiment (CERN, Berlin HMI, Caen GANIL, Munich TU, Warsaw,

Rossendorf FZ, Orsay IPN, Moscow INR, Rochester, Catania) is to study the production and decay of hot,

thermally excited nuclei produced with energetic antiprotons in order to obtain information on the bulk

properties of nuclei like heat capacity, specific heat, and phase transitions. In order to study these phenomena

of thermally excited nuclei it is desirable to produce the nuclei with a maximum of thermal excitation energy

and simultaneously minimal excitation of collective degrees of freedom like shape distortions, spin, and

compression. Furthermore, this excitation process should be fast in order to minimize cooling of the nucleus

during the initial excitation. The excitation process following annihilation of energetic antiprotons is currently

the best available method to meet conceptually these requirements (of course antideuterons would be much

better). The alternative method of heating nuclei with heavy ions is an order of magnitude slower than with

antiprotons and induces large shape distortions, compression, and high spin influencing strongly the thermal

decay of these nuclei.

In the experiment we used two 4 nn detector shells: an inner detector for all kinds of charged nuclear

particles and an outer shell for neutrons. The two detectors allow event by event the observation of the

evaporation chain of excited nuclei and thus provide a new and more precise access to the amount of energy

which is dissipated into thermal nuclear excitation.


With this new method we determined for the first time excitation energy distributions in massive nuclei

from reactions with energetic antiprotons, namely at the highest LEAR energy of 1.2 GeV. The distributions

show that the average excitation energy increases with the mass number from about 150 MeV for Cu to

380 MeV for U. But they also show that in the high-energy tails of the distribution with about 1% of the total

cross-section it is possible to transfer as much as 500 or 1000 MeV to aCu or U nucleus, respectively. For the

Cu nucleus this energy exceeds the total binding energy and consequently we observed the total dissociation

of this nucleus into light particles. For heavier nuclei from Ho to U, on the other hand, we observed a non-

negligible fission probability up to excitation energies close to 1 GeV. This result is of particular interest for

the study of nuclear fission at high excitation energy since the fissioning nucleus is formed with almost no

shape distortion, compression, or rotational excitation, which is completely different from heavy-ion-induced

fission.

In 1995 we also measured:

(1) inclusive energy spectra of emitted particles (n, p, pions, and kaons) at 1.22 GeV antiproton energy.

This data is needed for a detailed comparison of intra-nuclear cascade calculations of equilibrium

and pre-equilibrium emission of light particles as well as for further investigation of the unexpected

high n/p ratio found previously for antiproton annihilation at rest;

(il) inclusive neutron multiplicity distributions with 1.22 GeV protons in order to compare directly the

excitation of energetic protons and antiprotons.

PS209

The PS209 experiment (CERN, Grenoble ISN, Munich TU, Warsaw Univ., Warsaw INS) investigates the

antiprotonic atom X-rays with the objective of obtaining information on the nuclear periphery of heavy

(A > 40) nuclei. It is also expected that the experimental data collected will better determine the parameters of

the antiproton-nucleus potential, still poorly known for these nuclei. The motivation for the present

programme appeared after our previous finding (PS203) that the outer periphery of heavy isotopes of all

elements is most probably composed predominantly of neutrons. This conclusion was obtained from the

radiochemical investigation of nuclear reaction residues after stopped antiproton interaction with heavy

targets.

The observables of the present experiment, namely the strong-interaction-induced level widths and shifts

are determined by studying the X-ray spectra with high-resolution, high-purity germanium (HPGe) counters.

As the measured widths are directly related to the nuclear density where the antiproton annihilation takes

place, the study of the antiprotonic X-ray spectra, combined with our previous radiochemical results, should

considerably constrain the analysis of the matter distribution in heavy nuclei.

The strategy selected to achieve the objectives of the PS209 experiment is to measure, whenever possible,

the light and heavy isotope of the same element and to search for the isotopic differences in level widths and

shifts. These differences, if not due to the E2 resonance or trivial changes in nuclear properties, could be

attributed to the extended nuclear atmosphere in heavy isotopes of a given element.


During 1995 the following targets were investigated: S9Co, SENj, 6ON;, N], SAN], 1247, 128 Te, 130 Te,

Typ, M6yp, 197 Au, 208pp, Probably the most striking result of this experiment is the observation of a large

difference between "®Ni and ®*Ni of the strong interaction level widths (Fig. PS209-1). This difference is in

good agreement with the expectations, based on the Hartree-Fock-Bogoliubov calculations of the nuclear

periphery in these nuclei. These calculations indicate that at nuclear distances corresponding to the most

probable value of the antiproton annihilation probability the nuclear density in 64Nj is almost twice as large as

in °®Ni. This is due toa strong neutron halo present in 64Ni and absent in ”®Ni. Strong isotopic effects were

also observed in Te isotopes. In this case, however, the E2 resonance contributes substantially to the increase

of the level widths when the isotope mass increases.

2 E£ ee E S 350 F S 20 8: SE

300 F 175 &

250 E 150 F 200 = 125 E

150 E 'n 75

50 F 5 Q Ersaulis sul shi 0 nn Ba 5

2600 2650 2700 2750 2800 2600 2650 2700 2750 2800 channel channel

Fig. PS209-1: Isotopic effects in the antiprotonic X-rays of Ni isotopes. The left-hand

side peak (235 keV) is then =8—6 transition not affected by the strong interaction.

The right-hand side peak (237 keV) is the last observredn =6 > 5 transition.

Atomic Physics with Antiprotons

PS205

Experiment PS205 (Budapest, CERN, Munich TU, Okazaki, Tokyo) studies the unusually long lifetime of

antiprotons trapped in antiprotonic helium atoms. The first observation of a laser-induced resonant transition

in an antiprotonic atom in 1993 and the observation of a second transition in 1994 established beyond any

doubt the high-n high-! states of P-He**e” atoms as the source of the observed metastability. Highly

improved theoretical calculations by V. Korobov of Dubna of energy levels based on this model led to the

discovery of five new transitions in 1995, among them two in ’He.

Two of the new resonances were found in the same manner as the previous ones in slow extraction from

LEAR. Using MW/cm? dye laser pulses of about 30 ns duration, dipole transitions of the P-He**e” atom

were induced between metastable (solid lines in Fig. PS205-1) and non-metastable (dashed lines) atomic

states, effectively forcing the antiproton to annihilate on interrogation with the laser beam. The laser was

triggered each time a metastable atom was known to be present among the 10° He gas atoms in the target

vessel. As the laser wavelength is tuned through the resonance frequency, a sudden increase in the annihilation

rate occurs at the arrival time of the laser light as shown in Fig. PS205-2 for the two resonances found in ?He.


Another transition was found in *He at 529.621(2) nm by applying a double-resonance technique using

two simultaneous laser pulses. One was tuned to the known transition at X =470.724(2) nm

[n,! = (37,34) — (36,33)]. If the other pulse is tuned to the energy difference between the upper state (37,34)

and its ‘parent’ state (38,35) (cf. Fig. PS205-1), an enhancement in the resonance intensity can be observed

due to the forced depopulation of the (38,35) state.

1=32 33 34 35

= 597.259 1739

38

37

36

On" Aaıp) Aa ppm)

-100 50 0 50 | l 1 l

Av=0 v=3 v=3 7]

v=2 v=2 4 = Hu (38,35) - (37,34) | "He

v=2 v=2

Kordbbov (1995) u m (37,34) > (36,33)

v=3 v=23 7 u lı (38,34) — (37,33)

_n | °He v=2 v=2

u HH (36,33) > (8,32)

TIITTTTTTTTTOITT Io va4ı = 2 | (37,34) (38,38)

2 1 *He =] v=3

1 HH (37,35) I (98,34) | Fig. PS205-1: Upper: level diagram of antiprotonic helium indicating the five

transitions found in *He. Lower: comparison of theoretical predictions and

experimental results of all seven transitions observed in 3He and *He.

After a first test in 1994 a new analog method of detecting the delayed annihilation of p in helium by

using the fast extraction from LEAR was successfully used to find two ‘unfavoured’ transitions (those

changing the radial node number v=n-I!-1 by 2) in He in 1995. The transition probability of those

transitions pointing upwards in Fig. PS205-1 is about two orders of magnitude smaller than the previously

observed Av = 0 ones. Unfavoured transitions are difficult to find in slow extraction owing to the high laser

power necessary to excite the one metastable atom present at a given time. In the analog method, one laser

pulse can induce transitions in the whole sample of 10° metastable atoms. Another advantage of this method is

the fact that it allows the lasers to be fired at very early times after the formation of the atoms (which is not

possible in slow extraction because of the large trigger delay of the excimer lasers) and thus improves the

accurate study of the time dependence of populations, even in the case where the mean antiproton lifetime is

reduced due to the presence of impurities.


The lower part of Fig. PS205-1 gives a graphical comparison of the experimental values for the observed

transitions with their errors and theoretical calculations available before the experiment. The typical

discrepancy of 50 ppm even for unfavoured transitions is a big improvement over the initial accuracy of

1000 ppm available in 1993 and 1994. This difference, however, is now being accounted for by V. Korobov by

including relativistic corrections in his calculations and will soon reach the region of the experimental errors.

This shows the potential for future high-precision measurements on these atoms. As a first step, an experiment

is planned for 1996 to measure directly the ‘hyperfine splitting’ of one transition by using a 2-laser-microwave

triple resonance method. This measurement will lead to a precise measurement of physical properties of the

antiproton itself.

(38,34) > (37,33) (36,33) — (35,32)

o 400r 04 ao 300 \

5 so0| Sl b) = 300 = 200 - &. 200 ar 2 2 _ _ 5 100- 5 10[ SS OL, O Ol.

1500 2000 1500 2000 Time (ns) Time (ns)

z | < | T 2 057 2

& | £ 8 0.25- 3

e ol oO

a 593.38 593.39 a 463.94 463.95 Wavelength (nm) Wavelength (nm)

Fig. PS205-2: On-resonance time spectra of the 593.388 nm transition (a) and

the 463.947 nm transition (b) found in "He. The dependence of the resonance

intensity (i.e. the peak area divided by the total number of delayed events) on the

laser wavelength is shown in (c) and (d).

PS207

Experiment PS207 (CERN, Ioannina, Islamabad, Jülich, Neuchätel, Paris, PSI Villigen) measures the

characteristic X-ray from antiprotonic hydrogen and deuterium to extract the strong interaction parameters

from the shift and line broadening of the K-series and the L„ transitions. For the detection of the L, radiation,

the necessary energy resolution of AB/E = 10* is achieved with a Bragg crystal spectrometer. The response

functions have been measured with narrow antiprotonic X-ray lines, which are not affected by strong

interactions and where no electrons are left in the atom to avoid screening corrections. The transitions (5-4) in

antiprotonic “He and (13-12) in ?Ne fulfil these requirements and thus energy resolutions are obtained of

230 + 30 meV and 360 + 40 meV at 1.799 keV and 2.444 keV, respectively [Fig. PS207-1(a), (b)].

The L, transitions both from hydrogen and deuterium show a significant broadening as compared to the

calibration transitions from *He and 2PNe [Fig. PS207-1(c), (d)]. For hydrogen, the hadronic shift of the L,

transition is measured to be less than 60 meV as given by the experimental error. For the first time, a strong

interaction effect in antiprotonic deuterium could be observed. The best fit to the L,, line shape is obtained

with a single Voigt profile. Our result for the spin-averaged shift of &,,=-100+ 75 meV and for the

broadening of I’), = 570 £ 85 meV indicates a very strong absorption and (from the minus sign) a repulsion of


the 2p level, whereas the predictions for T',, vary from 70-500 meV, which is 2-15 times the spin-averaged

width of protonium. When fixing the electromagnetic splitting as predicted from QED, the description of the

line shape becomes very poor. In conclusion, the present measurement shows no evidence for a line splitting

of the order of the hadronic width.

The experiment will be continued with a high-statistics measurement of antiprotonic hydrogen.

n n

35 D*He(5-4) quartz 100 100} B?ONe(1 3-1 2) Si 111

30 Fr 1.799 keV spher. . 2.444 keV spher.

o5 1 T R=298m | 80F R=2.98m “ 2100 r 100

IV b)

0 Ban i l ma _ 2 ınn0ßsmi ra 0 l

0 _20 40 60 80 100 120 140 0 _20 40 60 80 100 120 140

oot PHI22) quartz10o 1 50182) si111 1.737 keV spher. 120 2.317 keV spher.

R=2.98m 100 R=2.98m 15 »100 2100

0 20 4 6 80 100 120 140 0 200 40 60 80 100 120 140 channels channels

Fig. PS207-1: Antiprotonic X-rays measured with the Bragg crystal spectrometer. (a),

(b) Measurement of the spectrometer response function with narrow antiprotonic

transitions. (c), (d) L., transitions from antiprotonic hydrogen and deuterium.

PS210

The experiment PS210 (Erlangen, Genoa, GSI-Darmstadt, KFA Jülich) has performed an experimental

search for H atoms production at the Low Energy Antiproton Ring (LEAR).

The production mechanism (Fig. PS210-1) is based on the interaction ofthe p beam circulating in LEAR

with a Xe gas jet target, where an e*e” pair can be created, and subsequently the P and e* can form an H

atom if their two velocities match. H atoms are neutral and leave the ring, while all circulating antiprotons

are deflected by the LEAR dipole. After leaving LEAR through a vacuum tube and a very thin window, the H

atoms are dissociated in a set of silicon detectors, in which the e* annihilates to produce two Y’s of 511 keV

back-to-back. These Y’s are detected in a system of 6 Nal crystals. The p is detected and measured in a

magnetic spectrometer.

The target and final-state detector were set up and calibrated for data taking in September/October 1995. A

few spills of antiprotons at 1940 MeV/c were taken per day. During a run time of 15 hours, 300 000 triggers

were recorded. Calibration data were also taken. The off-line data analysis took advantage of the dE/dx


measurement in silicon and the scintillation time-of-flight counters, and of the Nal response. Using LEAR and

the gas jet internal target also has the advantage that the source position and size is well known.

As a result, 11events with a clear H signature have been found, with an estimated background of

2 events. No previous production of H atoms has been reported. |

Silicon Counters e* Annihilation

endiIn, Mm.

a et ”. ” Antiproton a —> an

>

To Magnetic Spectrometer

Antihydrogen and Time-Of-Flight

\. Low Energy Antiproton Ring

(LEAR)

Fig. PS210-I: Principle of antihydrogen production and detection using an

internal Xe gas target in LEAR.

ISOLDE Programme

ISOLDE Target Developments

15343

The purpose of the Radioactive Ion Source Test (RIST)/IS343 project (Brighton, CERN, Daresbury,

Liverpool, Manchester, Rutherford, Surrey) is to build a high-power tantalum target for the production of

radioactive ion beams using the 800 MeV proton beam from the ISIS spallation neutron source at RAL. It is

hoped to test the target with up to 100 uA of proton current yielding a performance comparable with that of a

standard ISOLDE target. The RIST and ISOLDE targets are made from a tube 2 cm in diameter, 20 cm long

and filled (- 50% packing fraction) with thin (0.025 mm thick) tantalum foils. However, to dissipate the high

power (up to - 30 kW at 100 LA) from the proton beam, the RIST target contains a stack of foil discs whereas

the usual ISOLDE tantalum target contains rolls of tantalum foil, where the axes of both disc stack and rolls

are coincident with the proton beam axis. The RIST target discs have a central 7 mm diameter hole to allow

easy access of the radioactive particles from the foils to the centrally placed tungsten thermal ionizer.

In the first part of the test a target (RIST-I) was constructed and tested: the results were reported in last

year’s annual report. The RIST-I target provides an important benchmark for the RIST project and ensured that

the change in geometry was beneficial to the project. The conclusion of the target test was that the regular


RIST geometry did indeed result in shorter release times and that the yields were near to the top of the spread

of yields expected from a standard ISOLDE target.

Subsequently, a new target was made to investigate the balance between diffusion and effusion processes

in the release of radioactive ions. The new target (RIST-II) is essentially identical to the RIST-I target except

that the foil thickness has been increased by a factor of 4 while maintaining the 50% packing density, and

hence the gap between foils has been increased by a factor of 4. The total mass of the target is unchanged.

Such a change would be effective for RIST, reducing the number of cut foils in the target from 8000 to 2000.

It is hoped that the increased conductance of the new target over the original will further increase the

release times. However, this is likely to be element-dependent and tests are needed to confirm this hypothesis.

Nuclear Physics

15302

The 1S302/ISOLTRAP experiment (CERN, CSNSM, GSI, Mainz, Montreal, Warsaw) determines masses

of unstable nuclei with high accuracy using a Penning trap mass spectrometer.

One of the most fundamental aspects of an atomic nucleus is its mass or binding energy. The variation of

binding energy with the number of protons and neutrons is a very important clue concerning the nuclear

structure. Furthermore, accurate experimental mass values serve as a stringent test of nuclear models and help

to improve their predictive power for nuclear properties very far from stability.

The ISOLTRAP system installed at the on-line mass separator ISOLDE/CERN is a tandem Penning

trap mass spectrometer. The first of the two traps serves for bunching, cooling, and isobaric purification

of the ions delivered by ISOLDE. The accurate mass determination is performed in the second trap and is

carried out via the determination of the cyclotron frequency of the stored ions. The magnetic field of

the Penning trap is calibrated by measuring the well-known mass of a stable isotope. The high resolving power

of the spectrometer (m/Am(FWHM) - 10°) enables separation of nuclei in their ground or isomeric state as

well as isobars. For short-lived isotopes with a lifetime of 1 s and mass of m - 100 u an accuracy of typically

Am/m - 10° is achieved.

Up to 1994 more than 70 isotopes of alkali and alkali earth elements were investigated. Owing to improved

ISOLDE yields, it was possible to extend the mass measurements to isotopes very far from stability. The

shortest-lived isotope that has ever been stored and investigated in a Penning trap is 142Cs with a half-life of

T,; n7 1.8 s.

With an improved set-up (a new superconducting solenoid for the first trap), mass measurements of rare

earth elements in the vicinity of semi doubly magic 146Gd became possible in 1995. In total 21 isotopes in this

region were measured, eight masses were determined for the first time.

At the moment, an additional ion beam buncher, based on a Paul trap, is being installed. This system will

extend the applicability of ISOLTRAP to non-surface-ionizable elements.


15324

The 15324 Collaboration (Orsay, CERN) studies ??’Ra nuclear spectroscopy using 140 cluster

radioactivity. A Ra source was produced at the ISOLDE mass-separator GPS on-line using the 1 GeV

proton beam of the PS Booster synchrotron with a ThC target (55 g/cm? thick). A ?°°Ra source of 211 MBaq

was obtained by implanting the 223Ra + ?23Fr 60 keV ions into a carbon plate.

The source was transported to Orsay and the energy spectrum of 14C jons emitted from the source was

measured with the spectrometer SOLENO. The highest statistics (899 events) and the best energy resolution

(90 keV) obtained so far in cluster decay allow a real spectroscopic study for the first time. Hindrance factors

for transitions to the ground state and first excited state in ?°®Pb, and limits for the next three low-lying states

have been determined. The data can be explained by a parent wave function containing mainly a ij]n spherical

component, with small admixtures from 877%, jı5sp and gg orbitals.

15329

The origin of the anisotropy in the alpha-decay of oriented nuclei is being investigated by 15329 (Bonn,

CERN, Leuven, Lyon). Over the years several theories have been developed, but there is no agreement, for

example, on how the partial alpha-waves which build up the total wave function, and hence the angular

distribution of alpha particles emitted by oriented nuclei, are to be described. In addition, experimental data to

test and possibly improve these theories is very scarce. When, in the 1980s, the Leuven nuclear orientation

group carried out the first systematic study of anisotropy alpha decay, this triggered renewed theoretical

interest in the problem. The ISOLDE experiment 1S329 aims to provide additional and reliable experimental

data to test and, it is to be hoped, improve these theories.

The anisotropy data that were obtained for favoured alpha-transitions of oriented At, Rn and Fr isotopes in

our first two experimental runs have been carefully analysed. Comparing the resulting öy) mixing ratios

between the L=0 and L=2 partial alpha-waves with predictions from different theoretical models clearly

shows that for near-spherical nuclei the alpha-anisotropy is mainly determined by the nuclear structure (i.e.

pairing interaction and proton-neutron interaction) rather than by the deformation of the nucleus. In our last

run we measured the anisotropy for the favoured 9/2” — 9/27 alpha-transition of 1895;, 1918; and 193Bi. The

anisotropy was found to change sign between 191g; and !?3Bi and the data confirm the above conclusion. At

present detailed theoretical calculations, using different models, are being carried out for the alpha-transitions

that were observed, which should lead to a more detailed understanding of anisotropic alpha emission.

15332

The 15332 experiment (Buenos Aires, CERN, Grenoble, Lyon, Orsay, Paris, Strasbourg, Warsaw) allows

precise determination of transition multipolarities by measuring internal conversion electrons down to 2 keV

with a high energy resolution. Thus the nuclear structure of excited levels can be studied and compared with

theoretical predictions, providing a stringent test of nuclear models far from stability. High energy-resolution

electron measurements have been performed with a semi-circular spectrograph. In order to preserve high

resolution at low energy, the radioactive ion beam delivered by ISOLDE was slowed down from 60 kV

to 700 V before collection. The radioactive source was then moved into the spectrograph and a high voltage


(- 10kV) was applied to accelerate the conversion electrons emitted by the source in order to allow the very

low-energy electrons to reach the photographic film.

Up to now, two experiments have been performed using the molten lead target to produce Hg isotopes.

Energy and efficiency have been calibrated for both experiments using the highly produced 187 and

184 masses.

The purpose of the first experiment was the search of the M3 transitions de-exciting the isomeric states in

183p: and 18105. The aim of the measurement is to extract the B(M3) transition probability in order to test the

neutron configurations proposed to describe the isomeric and ground states of the doubly-odd nucleus !8*Au

by comparing the B(M3) values in !®pt, 18105, and !®*Au. !8Pt and !81Os nuclei were obtained from the

decay of the corresponding Hg. The electron energy range studied was 2-90 keV. Figure IS332-1 shows a

partial spectrum obtained from 18345 sources. The high quality of the data is illustrated by the electron lines

of the 16.0 keV transition in !®°Ir: the L, line is observed at 3.2 keV and the doublet M)-M;, which

corresponds to a 0.36 keV energy difference, is well separated.

90000

L, 35.0 kev "®Pt 179 1 45.1keV Os r Y 16.0 keV "®ır M " NO k 99.7 kov "Ir 2

60000 - Auger LMM Fe

30000 - K 115.3 kev '®Pı

47.6keV '®Pı 183 UL Ko6a kev '®Pı

N 0 T T r T I T T T T I T v.

0 500 1000

Fig. IS332-1: Partial electron spectrum obtained from 183g sources.

The isomeric M3 transition has been clearly observed in 183p, (see the detailed part of the spectrum where

its Lz electron line is indicated), but in 18105 only an upper limit of its absolute intensity could be extracted

from the electron spectrum. From the experimental data, we have evaluated the B(M3) reduced transition

probabilities and the corresponding Weisskopf hindrance factor: Fy (M3,v1n[521] > v772[514]) = 62(+25/

-13) for 18Pt and Fy (M3,v1n[1521] > v77[514]) 2 250 for 1810. The Fy value in !®°Pt is similar to that obtained in !8*Au: Fy (M3, Ihyn ® v]n[521] > Tihgn ® v7n[514]) - 52, which confirms the configurations

proposed for the isomeric and ground states in 184 Au. As regards the Fyy, value in 18195, it is higher than that

obtained in !83Pt, but consistent with the Fy known in !”?W: Fy (M3, vjn[521] — v77[514]) = 1800. Measurement with higher statistics would allow us to obtain a precise Fw value in 18105 and to determine

whether the Fy, (M3) values are sensitive to Z through the N = 105 isotones, or present an abrupt change

between 1810s and !83Pt. Preliminary values of these results were presented at the Conference on Exotic

Nuclei and Atomic Masses (ENAM 95).


The purpose of the second experiment was to establish spin and parity values of nuclear excited states of

the doubly-odd 182], nucleus in order to test a semi-microscopic rotor-plus-two-quasiparticle model in a

transitional region far from stability. The electron energy range was 2-100 keV. The quantitative analysis of

the electron spectra is still in progress but most of the electron lines have already been identified. Among them,

it is worth noting that a 25.8 keV level is very clearly observed. Its multipolarity can be unambiguously

determined as E2 and the spin and parity values I" = 3* deduced for the 182], ground state. The 3* ground state

and the 25.8 keV excited level have then the rrhy,, ® v1,2[521] configuration in which the proton and neutron

movements are decoupled from the core movement. In this case, the corresponding rotational band, called

doubly decoupled band, is formed by states with Al=2 linked by E2 transitions. The E2 25.8 keV, first

member 5* — 3* of such an E2 cascade, is observed for the first time in Ir isotopes. The existence of the 3*

ground state at only 25.8 keV below the 5* state is in perfect agreement with the theoretical predictions.

15338

The 15338 Collaboration (Bergen, CERN, Goteborg, Mainz, Oslo, Strasbourg CRN, Studsvik, Lyon,

Warsaw) determines single-neutron states in 133Sn, at the doubiy-closed-shell nucleus 1325n, by measuring

y-rays in coincidence with delayed neutrons following the B-decay of 134. The single-neutron states are of

fundamental importance as tests of the nuclear shell model, and are important input parameters for nuclear

shell-model calculations.

Previous attempts to determine the single-neutron states in 135n by investigating the ‘normal’ B-decay of

133]n failed because of unfavourable decay properties of 133[n. This nuclide mainly decays through the

emission of delayed neutrons, or through a ground-state transition. Hence, the single-neutron states in 1335n

could not be identified. However, the same states are populated via delayed neutrons from 134m. By

investigating n-coincidences at mass-number 134 at PSB-ISOLDE, transitions depopulating these states were

uniquely identified.

The experiments were performed using a uranium carbide target equipped with a surface ionizer.

Five neutron coincident Y-transitions were identified. Three of these, at 853.7 keV, 1560.9 keV and

2004.6 keV were assigned as ground-state transitions. A transition at 802 keV is tentatively suggested to be

the pıp — P3n transition.

Hence, four out of six expected single-neutron states in !?°Sn have been characterized firmly and the pır

state is ambiguously suggested (see Fig. 1S338-1). The remaining ij3,, state is probably positioned above the

133Sn neutron separation energy at 2.45 MeV.


2004

.6 (

5,19)

fon S 2004.6

Ss 8 Ss a5

Pır © 8 (1655.7) Ngp _ 1560.9

S 2

n cn

ap & 853,7

fn ! Y ! 0.0 1335

Fig. IS338-1: The states observed in "??Sn. The y-ray intensities given in the

figure refer to !?*In (first digit) and !>’In (second digit), respectively. The

absolute intensities of the 1560.9 keV transition is 5-10%/decay of ! 34m and

- 0.5%/decay of !?3In.

15346

15346/MISTRAL (Mass measurements at ISolde using a Transmission RAdiofrequency spectrometer on-

Line) is a new programme for high-precision mass measurements of very short-lived nuclides. Such

measurements are interesting for nuclear structure and for improving nuclear mass models for more reliable

mass extrapolations into areas of astrophysical interest.

At the heart of MISTRAL is a high-resolution Smith spectrometer which employs coherent radiofrequency

modulations of the kinetic energy of ions orbiting a 1-m diameter homogeneous annular magnetic field. The

cyclotron frequency (whence, the mass) is determined from the RF frequency for which two successive

modulations cancel and the ions pass through a 0.4 mm slit at the exit of the spectrometer. Mass values are

obtained by comparing the cyclotron frequencies with those of reference masses measured in fast alternating

cycles.

With a resolving power greater than 10°, the measurement accuracy is expected to be of the order of

5x 10’ (0.5 keV/A). The spectrometer transmission will be about 0.5% offering over 100 measurement

candidates from the ISOLDE production repertoire. As the ISOLDE beam is used directly, the technique is

universal and there are no half-life limitations due to collection or re-ionization. Thus, MISTRAL is very

complementary to the existing ISIOLTRAP experiment with which there is close collaboration.


MISTRAL is scheduled for installation in the new beam hall extension in late 1996 with first beam times

foreseen for mid 1997.

Solid-State Physics

15325

1S325 investigates impurities and defects in II-VI semiconductors with combined electrical, optical, and

nuclear methods (Berlin, Berlin HMI, CERN, Jena, Lisbon). In II-VI semiconductors, severe doping problems

prevent or aggravate the adjustment of conductivity type and magnitude. The present experiment uses standard

techniques of electrical and optical semiconductor spectroscopy like PAC, Hall, CV profiling, DLTS and PL to

study doping effects. Radioactive isotopes from ISOLDE are used as probes for nuclear techniques like

transmutation doping, i.e. the desired doping is the daughter element of the implanted isotope. Starting from a

substitutional host element, the doping is created in a well-defined way without disturbing processes.

As a first step, the incorporation and annealing of Cd in CdTe was studied. Next, the doping effects due to

Ag or In daughter elements were demonstrated by CV profiling in CdTe and ZnTe. In all cases, the doping

effect which is expected from the chemical nature of these elements was observed, i.e. competing effects like

self-compensation, which usually prevent the desired effect, are completely avoided.

15345

The 15345 Collaboration (Konstanz, Berlin, Bonn, Duisburg, Erlangen, Freiburg, Jena, Lisbon, Caen,

Paris, Troitzk, CERN) studies the hydrogen diffusion and hydrogen passivation mechanism in binary and

ternary III-V semiconductors. For this purpose nuclear methods like yy- or Perturbed Angular Correlation, for

example, are combined with electrical techniques, like Hall effect measurements. Formation, structure, and

stability of next nearest pairs formed by Cd acceptors and H donors have been observed in ternary compound

like AlxGal-xAs, GaxIn1-xP and InxGal-xAs. The characteristic parameters of these pairs directly reflect the

compound lattice structure. Future experiments will focus on the stability of the Cd-H pairs in these systems

especially in dependence on the stoichiometry. For the first time the PAC isotope I cqg — In was

successfully used at ISOLDE. By low-energy H* implantation INcg-H pairs are formed in InAs and InP and

after the radioactive decay into 117m it becomes possible to observe the dynamic behaviour of free H* and/or

H°. In further experiments the temperature as well as the background doping of the samples will be varied to

deduce directly the migration energy of hydrogen.

Biochemistry and Biomedicine

15313

The 15313 Collaboration (MPI Martinsried, Munich TU) has prepared Cd and Hg derivatives of the multi-

copper enzymes ascorbate oxidase and laccase as well as the small blue copper proteins (electron transfer

proteins) azurin, plastocyanin, and stellacyanin with the short-lived radioisotopes Ilmog (Tjn = 49 min) and


mpg (Tj» = 43 min) supplied by the isotope separator ISOLDE. The nuclear quadrupole interaction (NQI)

of mag and 19myg in these proteins was monitored by time differential perturbed angular correlation of

y-rays (TDPAC).

In the Hg derivatives of the multi-copper proteins three sites have been detected and assigned to the

so-called type 1, type 2, and type 3 metal sites. Our results on the Cd derivatives show that Cd does not

reconstitute the type 2 site at all. The type 1 site is clearly identified by comparing the NQI data with those of

small blue copper proteins containing the type 1 site only.

The type 1 site in the native proteins azurin, plastocyanin, and stellacyanin as well as various mutants of

azurin and plastocyanin have been studied with both !!!MCq and !?’"Hg TDPAC. The type 1 metal co-

ordination appears to be mainly three-fold planar by a cysteine and two histidines (bond length =2 Ä). A

longer approach is made by a methionine perpendicular to the plane: bond length = 3 Ä. In order to assess its

role in the metal co-ordination, the methionine was exchanged against other ligands via site-directed

mutagenesis. This has a small effect on the NQI only, which is easily understood in terms of a small metal

displacement out of the plane. This is a clear indication that the methionine does not bind to the metal but may

have some importance for the fine tuning of this “entatic’ metal coordination.

The electric field gradient tensor components of the Ilmagy mpg NQls in type 1 and type 3 sites of the

investigated proteins appear to scale for the Imcog and 199mpg derivatives (see Fig. IS313-1) indicating a

torsional rigidity of the metal site.

90 ——ı1777n7n171n7n771177

A 19®M}g-Derivatives 4 80 L o !imcg.Derivatives |

70 | . 1 } , 4

_ 60L AO Typen.” >TE 50 | nr % & LAC Type2

30 L Ba 2 -

20 | SR | r E

; 0 2 AG Type3__, Lt L_ 1 LI.

0 00 0 0 50 60 7 8 90 Vito N

Fig. IS313-1: The diagram of the electric field gradient tensor components |V,,|

and |V,,| ofthe investigated Hlmcq and !?? "Hg derivatives showing the scaling

of the IV,,| and |V,,| upon metal exchange.


15348

The 18348 Collaboration (Boston, Cambridge, Leipzig) studies mercury ions and organomercurial

reagents which are extremely toxic due to their affınity for thiol groups. Many bacteria contain an elaborate

detoxification system for a metabolic conversion of Hg’* and organomercurials to non-toxic elemental He’.

The main components of the enzymatic mercury detoxification are the regulatory protein MerR, the

organomercurial lyase MerB, and the mercuric ion reductase MerA (Fig. IS348-1).

merR OP merT merP merA merB merD Mer R: Regulatory Protein

es Mer B: Organomercurial Lyase \ % RHgX + H*+ X" RH + HQX,

?

Hg(0) Mer A: Mercury Ion Reductase Lyase Hg(il) — Hg(0)

tt DOM oO

Cytoplasm

Inner Membrane

Periplasm

merp .Hglil)

Hg-S-Cysteing-Coordination (2-, 3-, 4-fold)? Reaction Mechanism?

Fig. IS348-I: Schematic model of the mercury detoxification system of the

plasmid pDU 1358.

The Merk protein, a mercury-responsive genetic switch, controls the expression of the other detoxification

proteins Mer*. MerR exhibits a unique selectivity and ultrasensitivity in stimulating the production of the

Mer* proteins: 10° of Hg* are sufficient to turn on the detoxification system. The molecular origin of the

MerR properties are postulated to arise from an unusual mercuric ion coordination environment. In 1995, we

could demonstrate that the measurement of the nuclear quadrupole interaction (NQI) of dmg (supplied by

the isotope separator ISOLDE) via time differential perturbed angular correlation (TDPAC) is a powerful tool

to distinguish between 2-, 3-, 4-fold Hg coordination, and furthermore yields information concerning

structural distortions within a given coordination number. By comparing the NQls of mpg between model

compounds and Hg-Merk, the He’* coordination is identified unambiguously as 3-fold. This quite rare Hg’

coordination was also detected in the almost inaccessible regime of trace amounts of He’. In order to

elucidate the interaction of the Hg?*-MerR complex with the DNA 199myg x-DPAC studies are currently

under way.

Preliminary, but promising experiments to reveal the reaction path of the MerA protein by detecting

different Hg coordination spheres via their characteristic NQI signature have already been carried out.


15350

The 15350 experiment (Leipzig) is studying humic substances which are ubiquitous in water and soil and

act as complexing agents for different heavy metals, e.g. Cd?*, Hg**. Toxicity, reactivity, fixation, and

migration are therefore strongly influenced by the interactions between heavy metals and humic substances.

Humic substances derive from postmortal materials such as rotten plants, have dark colours, and usually

a molecular weight between 500 and 10 000 Da. Complex formation studies with different heavy metal ions

indicate at least two different kinds of metal sites. Usually, these studies are restricted to heavy metal

concentrations 2 to 3 orders of magnitude higher than the natural heavy metal abundance. We use nuclear

quadrupole interaction of Himcg and mpg monitored by time differential perturbed angular correlation

of y-rays (TDPAC) for the Cd and Hg speciation in humic substances. The short-lived radioisotopes imog

(Tjn = 49 min) and mpg (Tjn =43 min) are supplied by the isotope separator ISOLDE. Whereas in the

case of Hg a more specific binding with lower Hg concenträtions was observed, the Cd data showed only

unspecific binding even in the regime of trace amounts of Cd. Currently, selective blocking studies of the

functional important groups to identify the Hg ligands in humic substances are under way.

R&D Projects

RD7 - Proposal for R&D on a Central Tracking Detector Based on Scintillating Fibres |

The RD7 Collaboration (CERN; Lab. de Genie Electrique, CNRS, Toulouse; Kernforschungszentrum,

Karlsruhe; Kuraray Co., Tokyo; DESY-IfH, Zeuthen; Wuppertal Univ.) continued the investigation and

improvement of the properties of scintillating fibres for particle tracking and the development of a new

optoelectronic read-out, aimed at demonstrating the feasibility of such a detector in present and future high-

energy physics experiments. For details see the Optical Fibres Group section.

RDS8 - Development of GaAs Detectors for Physics at LHC

The main objectives of the RD8 Collaboration (RWTH Aachen; ANSTO Sydney; INFN, Bologna Univ.;

INFN, Florence Univ.; Freiburg Univ.; Glasgow Univ.; Lancaster Univ.; Modena Univ.; Czech Technical and

Charles Univ. and Inst. Phys., Prague; IHEP, Protvino; RAL; Sheffield Univ.; Udine Univ.; SPTI, Tomsk; Inst.

Semiconductor Phys., Vilnius) are:

— fabrication and testing of simple GaAs detectors for charged particles and X-rays,

— understanding the properties and limitations of these simple pad detectors,

— investigation of alternative wafer materials and detector fabrication technologies,

— fabrication and testing of prototype microstrip detectors to LHC specifications,

— design, fabrication and testing of GaAs pixel detectors,

— demonstration of the radiation-hardness of GaAs detectors and understanding its limitations,

— development of GaAs low-noise, low-power preamplifiers adapted to the above GaAs detectors,


— encouraging the commercial production of GaAs microstrip detectors,

— developing a detailed understanding of the costs of commercial detectors,

— identifying the possible commercial applications of GaAs detectors.

Substantial progress continues to be made in the pursuit of these goals. Improvements have been made in

wafer processing, contact preparation and the understanding of charge transport and trapping and radiation

damage induced by - 1 MeV neutrons and by high-energy protons and pions in GaAs. Considerable work still

remains to be done, however, particularly in the area of radiation hardness to high-energy charged particles

and in optimization of wafer material choice, device design, fabrication process and cost, in co-operation with

potential commercial suppliers.

Continuing investigation of various GaAs substrate materials is now addressing such issues as the

influence of dopant materials and of annealing techniques, particularly in irradiated material.

GaAs microstrip detectors, made ‘in-house’ and by Alenia SpA (Rome), EEV (Chelmsford) and the SPTI

Tomsk, were tested in CERN test beams during 1995. Systematic analysis will enhance the understanding of

microstrip detectors and permit detailed modelling of their behaviour and optimization of detector parameters

in future designs.

GaAs pixel detectors fabricated in Glasgow and commercially (by Alenia SpA), were bump-bonded to

Omega2 read-out chips and tested in high-energy particle beams. The beam profile from a three layer GaAs

‘telescope’ is shown, together with an ‘event’ initiated by a single beam particle, in Fig. RD8-1.

Plane

0 Pl

ane

1 Pl

ane

2 Single Event Beam profiles

Fig. RD8-1: Pixel ‘hits’ in a single event (left) and beam profile (right) obtained from

a telescope of three GaAs pixel detector arrays coupled to Omega2 read-out chips.


GaAs Schottky detectors now consistently achieve charge collection efficiencies close to 100% and are

also operational at temperatures down to -10°C. The radiation hardness to y-rays is already adequate for LHC

applications. The sensitivity to high-energy pions and protons is higher than in silicon for reasons which are

still not fully understood. Annealing studies (see Fig. RD8-2a), and material characterization of irradiated

detectors are already in progress. The charge collection efficiency, signal-to-noise ratio and position resolution

of ‘in-house’ and commercial GaAs microstrip detectors before irradiation and after neutron irradiation up to

fluences - 101* cm? appear adequate for LHC operation (see Fig. RD8-2b). GaAs pixel detectors have also

demonstrated their capabilities for both high-energy and medical physics applications.

1007.

10

OO

oO ersehnte

T T

60 nn nen

> oO T

a als, &

oO

—

N

OO O0

waelarsı Char

ge co

llec

tion

efficiency (%

)

3

Charge collection efficiency (%)

m Pre-Iradiation (approx.20IC) e Post-Irradiation (-10IC) z— 4 Post-Irradiation & Annealing (-10!C)

0 100 200 300 400 500 600 0 T Bias (V) Fluence

(a) (b)

TIrYTTT

Fig. RD8-2: (a) Charge collection efficiency vs. bias at 20°C (solid squares) and

at-I10°C for a 120 um thick pad detector, before and after annealing at 450°C for

2 minutes, (b) charge collection efficiency vs. fluence (x 1 01*/cm?) for 24 GeV

protons (triangles, two samples) and - I MeV neutrons (circles) irradiation.

Development of GaAs electronics in Aachen, Freiburg and Vilnius has already led to prototype GaAs

preamplifiers suitable for GaAs detectors. Theoretical and experimental studies of noise in GaAs, the

characterization of unirradiated and irradiated detectors and possible methods of enhancing radiation hardness

have also been carried out, together with modelling of radiation damage in deep-level doped GaAs.

RD9 — A Demonstrator Analogue Signal-Processing Circuit in a Radiation-Hard SOI-CMOS Technology

The RD9 group at CERN further evaluated the HSOI3-HD radiation-hard 1.2 um SOI-CMOS integrated-

circuit technology of Thomson Composants Sp&ciaux (TCS, Grenoble) and, in parallel, designed some test

structures in other technologies, DMILL and standard CMOS, which have also been subjected to the

irradiation testing. An improved analogue memory circuit and an ADC were produced in SOI. Before

irradiation both circuits performed according to simulations. Discrepancies occurred after 10 Mrad irradiation,

while the noise was higher throughout than that in a standard technology. Recently TCS announced the

withdrawal of the SOI technologies. Alternatives have to be sought. For some applications the DMILL

technology was found to have excellent noise performance due to the availabilıty of a bipolar transistor. The

survival of some standard sub-micron electronics chips under radiation may be better than expected because

advanced processing technologies use very thin oxides.


RD11 - Embedded Architectures for Second-Level Triggering in LHC Experiments (EAST) |

The RD11 project (NIKHEF, Amsterdam; Inst. for Atomic Physics, Bucharest; KFKI Res. Inst. of Physics,

Budapest; CERN; Niels Bohr Inst., Copenhagen; Inst. Nucl. Phys., Cracow; RAL; JINR, Dubna; Friedrich-

Schiller-Univ., Jena; LIP, Lisbon; RHBNC, London; UCL; Manchester Univ.; Mannheim Univ.; Inst.

Computer & Infor. Sci., Prague; Weizmann Inst., Rehovot; Univ. Fed. Rio de Janeiro; Utrecht Univ.; DESY-

IHEP, Zeuthen) was terminated as a separate R&D activity at the end of 1995. The decomposition of the

second-level trigger into front-end buffering and collection of raw data for regions of interest; feature

extraction, i.e. the local processing of data in a region of interest of a subdetector; and making a global

decision, i.e. combining all subdetectors and event processing, has been taken over by ATLAS. The

implementation options (farm-based and data-driven) are still under exploration.

In more detail, the activities of EAST in 1995 were the following:

Pipelined data-driven systems were exhaustively demonstrated: a TRT Router, the Enable processor

and DecPerle performed well in beam and lab tests. A design allowing the implementation of all trigger

algorithms will be tested in 1996 as part of the ATLAS programme. These FPGA-based devices

demonstrated the ability to keep up with the 100 kHz input rate for all algorithm parts, and could thus

implement a full level-2 trigger.

Components of a farm-based solution, based on DSPs (C40 from Texas Instruments) and DS-links with

a C104 switch (C104 from Inmos), were brought to CERN for testing in the laboratory and in the

ATLAS test beam; these tests will be continued with more complete equipment in 1996. SCI interfaces

and a computer farm, based on Alpha processors, will also be tested.

A model written in the simulation language Modsim II was developed, describing farm-based

solutions, in particular the C40/C104-based version; it will be finely tuned so that extrapolation to a full

system becomes possible.

Participation in the AFRODITE project continued, allowing a detailed assessment of a formal object-

oriented language (VDM++) for the applications of hardware and software specification of the level-2

trigger. AFRODITE was completed successfully at the end of 1995.

An improved version of the SLATE emulator was designed and built; all existing SLATEs are now

being upgraded to satisfy the improved specifications and will be available for future testing.

A benchmark suite for measuring combined communication/computing performance of parallel

systems was developed, and is now being used to evaluate candidates for computer farms, in particular

large commercial parallel systems (HPCN systems).

RD12 - Timing, Trigger and Control (TTC) Systems for LHC Detectors

The RD12 Collaboration was restructured to concentrate on TTC system development and now comprises

members from CERN; GSI, Darmstadt; Honeywell, Aldermaston; Lemo, Ecublens and Worthing; Paris Univ.

VI and VI; RAL; and UCLA. The project includes representatives from ALICE, ATLAS, CMS and LHC-B,

as well as industrial partners.


All the subdetectors of the proposed LHC experiments require quite extensive distribution systems for the

transmission of timing, trigger and control signals to large numbers of front-end electronics controllers from a

single location in the vicinity of the central trigger processor. The TTC systems must control the detector

synchronization and deliver the necessary fast signals and messages that are phased with the LHC clock, orbit

or bunch structure. These include the bunch-crossing clock, level-1 trigger decisions, bunch and event

numbers, as well as test signals and broadcast commands. A common solution to this TTC system requirement

is expected to result in important economies of scale and permit a rationalization of the development,

operational and support efforts required.

RD12 is developing a multifunction optoelectronic TTC distribution system which can meet the

requirements of the different subdetectors of the LHC experiments. A laser transmitter, modulator, encoder

and VMEbus interface are being developed as well as a subminiature radiation-hard optical-fibre connector,

active device mount and photodetector/preamplifier. A timing receiver (ASIC) is being designed, which will

generate the full range of decoded signals for front-end electronics controllers from a single input.

The system incorporates programmable coarse and fine de-skew facilities to compensate for different

particle flight times and detector, electronics, propagation and test-generator delays. It can also transmit

asynchronous slow controls and data such as individually-addressed channel enables and calibration

parameters to several thousand destinations.

During 1995 several TTC laser transmitter crates were produced, a preliminary version of the VMEbus

interface (TTCvi) was developed and the timing receiver ASIC (TTCrx) was designed and submitted for

fabrication. Prototype versions of the subminiature ‘*RD12’ optical connector and active-device mount were

manufactured by our industrial partners and irradiation tests of the photodetector/preamplifier commenced,

with satisfactory results.

WWW home page: http://www.cern.ch/TTC/intro.html

RD13 - A Scalable Data-Taking System at a Test Beam for LHC

The RD13 Collaboration (CERN; IN2P3, Marseille; Oxford Univ.; Budker Inst., Novosibirsk; INFN, Pavia

Univ.) installed a test-beam read-out facility for the simultaneous testing of LHC detectors, trigger and read-

out electronics, and developed the supporting architecture in a multiprocessor environment. The aim of the

project is to build a system which incorporates all the functionality of a complete read-out chain. Emphasis is

put on a highly modular design, such that new hardware and software developments can be conveniently

introduced. Exploiting this modularity, evolution of the set-up will be driven by technological progress.

The RD13 DAQ system has evolved to cope with the demanding requirements of a configurable multi-

detector set-up. The latest version of the RD13 DAQ system was used in the H8 test-beam area by ATLAS

sub-detectors during 1995. Since June 1994, a number of functions have been completed and new features

have been added, some of which are outlined below.


rom local detector acgı

it for tie contm) om

ped by ie UN D

during the past year second-

ihem to Ihe requureme

ihe analogue chain, an Improved version ol

Ze:

farmance oil

st wien

n emvironme

leg

u DE

u u su

£} # IMENEE

LPT 388

namely a fast and low-noise front-end amplifier, and analogue pipeline, a signal-processing element and a

multiplexer. Two 128 channel chips were produced, one (APV5) in radiation-hard form containing all the

functions required, and the other (FELEX) in a non-hardened process with a shorter pipeline memory and

without an on-chip multiplexer. A 32 channel prototype was also produced in a second radiation-hard

technology (DMILL).

The APV5 was implemented in the Harris AVLSI-RH 1.2 um bulk CMOS radiation-hardened process

containing 128 channels of amplifiers, pipeline and APSP with a multiplexer. The chip is fully functional but

there are a number of areas where improvements are required although a signal-to-noise ratio of 16 was

achieved in peak mode with 50 ns shaping using a 6 cm 350 ‚im thick microstrip detector read-out at 50 um

pitch. The development continues in the context of the CMS experiment. The architecture of the FELIX chip

was developed in the AMS 1.2 um CMOS process, using the same functions as the APV5 except that

multiplexing is done off-chip. The pipeline uniformity and overall stability of the chip is excellent and it was

used successfully in several beam tests in summer and autumn 1995. The H8 beam test yielded a signal-to-

noise ratio of 33 in peak mode (75 ns) with a 6 cm detector.

Detailed studies were carried out on transistors from both Harris and DMILL processes and amplifiers

from Harris runs (Figs. RD20-1 and RD20-2). The general conclusions are that both processes are very

similar in terms of noise and hardness and appear to be among the best CMOS/SOI processes so far

investigated for LHC applications.

106 rate an acceptor at

105 certain level to 6 cm"!

of — o/0;=0

408 Donor curves

E B=0.0007 cm’! S eo 1% gs

S 4nl 3" (co 8 10 s (CO)

10°! V

10?

10° #4 -03 -0.2 -01 00 01 02 03 04

Defect energy level (eV)

Fig. RD20-1: The lines ascending to the right show the introduction rate for an

acceptor state at a given energy level required to give B= 0.016 cm”! for different

assumptions of electron and hole cross-sections. Circles show known or possible

acceptor state introduction rates from the model, squares show known donors.

The lines ascending to the left show the introduction rate of donor states required

to be consistent with the presence of CO and CC states; they correspond to

Baonor = 0.0007 cm’.


: | Noise spectral density of 1.2 um PMOS transistors at 500 uA

Tb... 50.4 onlble 0 uudunduunhuiehbuue mann ben 9 Hals

A PERIWER 475° fe DMILL |

R PUR : . |-®- Thomson SOI

’ EI FEEERE dd ieiiii

10° 10° 10° 107 f (Hz)

Fig. RD20-2: A comparison of the noise spectral density of PMOS transistors of

dimensions similar to those used in the RD20 amplifier from different radiation-

hard processes. The DMILL and Harris transistor results are from measurements

made by RD2DO.

Work continued on detector radiation-tolerance, with the emphasis on bulk-damage issues where there was

significant progress ın understanding its microscopic origins in terms of a model based on deep acceptor

levels. This appears to explain most of the experimental results. Candidates for the traps were tentatively

identified as vacancy-oxygen complexes with the aid of numerical simulations. The concentration of oxygen

and carbon in the silicon has a significant effect on the concentration of deep traps, and may enable the

hardness of detectors to be improved.

Recent publications are listed in the final status report, CERN/LHCC 96-2. There is an RD20 WWW page

with a list of technical notes and papers. The address is: http://albert.hep.ph.ic.ac.uk/RD20/RD20.html.

RD23 —- Optoeletronic Analogue Signal Transfer for LHC Detectors

The RD23 project is aimed at developing analogue optical links, based on electro-optic intensity

modulators, for signal transfer between LHC-detector front-end and read-out electronics. The collaboration

consists of 11 research institutes (CERN; Birmingham Univ.; EPF, Lausanne; Lecce Univ.; Firenze Univ.;

MASPEC, Parma; IC, London; Lund Univ.; Siegen Univ.; RAL) and three industrial partners (GEC Marconi,

Europtics, ITALTEL), in close contact with both the ATLAS and CMS experiments. The link architecture is

based on reflective Fabry-Perot modulators and transceivers (semiconductor lasers, photodiodes, optical

splitters, couplers and amplifiers) connected together by single-mode optical fibres. The modulators, mounted

on the front-end hybrids, convert the pipeline sampled voltages into optical signals by modulating the

continuous-wave light emitted by the lasers (placed on the read-out board) and reflecting it back to the

photoreceivers. This configuration matches the requirements of radiation hardness, power dissipation and

cabling bulk in the front ends. The operation wavelength is set at the standard telecommunications value of

1.55 um.


Progress on the modulator side included the comparative evaluation of 48 channels and preliminary

tests of the device’s photoreceiver characteristics. On the transceiver side passive waveguiding components

were fabricated in an advanced glass-on-silicon technology and tested in view of their hybridization into a

compact package. Extensive Y-ray irradiation tests were carried out, alternating low dose rate (dD/dt - 600

rad/h), recovery, and high dose rate (dD/dt - 200 krad/h) sequences. The total observation time was - 5000 h,

with an accumulated dose of - 20 Mrad. A complete 4-channel link was continuously evaluated during

transmitter irradiation, yielding information on system long-term stability and modulator/photoreceiver

radiation resistance. Single mode fibres of various types and semiconductor lasers were also irradiated and

characterized as a function of dose and rate. Besides the analogue mode of operation, the digital behaviour of

the link was evaluated, demonstrating that bit error ratios well below 10 1! can be achieved at clock rates of

100 Mbit/s.

Future activities will include the development of an optical link demonstrator with 6 analogue (and/or

digital) transmitters and 2 digital receivers; the growth and characterization of modulator arrays with

8 channels; the study of a compact hybrid transceiver, the hybridization of a PIN photodiode with an

integrated transimpedance amplifier; and the continuation of the irradiation tests, this time with neutrons.

RD24 - Application of the Scalable Coherent Interface to Data Acquisition at LHC

The RD24 Collaboration (CERN; Oslo Univ.; LBL; INFN, Lecce; IHEP, Protvino; Valencia Poly. Univ.;

IFIC, Valencia; RAL; INFN, Rome Univ.; Manchester Univ.; CIEMAT, Madrid; Dolphin Interconnect

Solutions A.S., Oslo; DEC Joint Project at CERN; Thomson-TCS, Orsay) is involved in the evaluation and

implementation process of the IEEE 1596/ANSVISO-IEC Standard, called Scalable Coherent Interface (SCH,

which is proposed as scalable Data Acquistion Technology for LHC. SCI has become the computer

interconnect for next-generation industry desktop multiprocessors and for high-end MPP architectures due to

its very high bandwidth and very low latency features. Commercial SCI products were proposed, influenced

and evaluated by RD24 and a series of SCI CMOS chip technologies are now being integrated into DAQ

components. A crate interconnect and a computer interconnect, implemented as SCI bridges to the industry

PCI bus, are under evaluation. The successful collaboration with computer industry and EC funded projects is

continuing.

RD24 performed extensive modelling of SCI-based DAQ architectures, which confirmed SCT’s intrinsic

scaling up to the LHC bandwidth requirements. The technical proposals of both ATLAS and ALICE refer to

SCI as a candidate for inclusion in their DAQ systems. The packet routing properties of SCI switches,

investigated within the same modelling work, were fed into a EUREKA-funded industry collaboration called

TOPSCI, with the result that the next generation SCI CMOS chip is built according to the suggestions of

RD24, performing at 1 Gbyte/s. This chip will be a universal building block of very high rate SCI switches.

The crate interconnect in LHC requires that large numbers of bus units (VMEbus) participate

simultaneously in the event transfer without mutual blocking, at event rates of 1 kHz and up to 100 Mbyte/s

throughput. In order to keep the buffers small, the transfer latency should be much less than the average event

delay, i.e. - 1-10 us. RD24, in close collaboration with the STAR experiment, has built a PCI-SCI bridge,

based on a 200 Mbyte/s SCI CMOS chip which fulfils these requirements with the addition of an event-scan

DMA engine. The bridge card can be added to VME boards with mezzanine extensions according to the new

IEEE 1386 standard (PMC). The design of the PCI-SCI bridge was performed in VHDL language at CERN


and synthesized into high-density FPGAs. It constitutes the first PMC designed under CERN copyright and is

being transferred to industry. Test software is being developed under the real time UNIX LYNX-OS system.

The computer interconnect for LHC connects a CPU farm to the output of an event builder. The most

efficient event-collection concept is the globally shared memory, which, like in a single computer memory,

enables event data to be sorted into common address ranges of the global CPU-farm. Shared memory over SCI

was implemented and demonstrated by RD24 on SUN computers, using commercial SBUS-SCI interfaces.

RD24 also designed a PCI-SCI bridge for INTEL and DEC computers. The crate and computer interconnects

can be linked together via SCI ringlets and SCI switches, for DAQ test systems or to build a large DAQ

system. Evaluation and development of application software for the computer interconnect under the LINUX

and Windows-NT operating systems are underway.

The DSP-SCI interface designed by RD24 in collaboration with IFIC Valencia was produced in prototype

quantities and is going to be tested in the ATLAS T2 demonstrator.

The physical layers of SCI, in particular the 1.4 Gbit serial and 400 Mbit 8-bit parallel fibre-optics

solutions were extensively studied. These activities are coordinated within an ISO-IEC working group,

chaired by RD24, and hosted by ESONE. This standardization effort aims to maintain the compatibility of

physical layers from different manufacturers.

RD26 - Study of Solid Photocathodes Operated at Atmospheric Pressure in Fast RICH Detectors (RICH & Cs)

In the RD26 Collaboration (INFN, Bari Poly.; CERN; LIP, Coimbra Univ.; Giessen; EPF, Lausanne; Lund;

INR, Moscow; TU, Munich; INFN, Padua Univ.; EP, Palaiseau; INFN, Rome Sanita; Rehovot Weizmann Inst.;

DAPNIA; INFN, Trieste Univ.; Zagreb Rudjer Boskovic Inst.), work on the production of photocathodes was

pursued, aiming to reproduce a CsI quantum efficiency as high as the one achieved at the end 1994, i.e. 0.19 at

180 nm.

Four new large photocathodes were produced and tested in a fast RICH at the PS T11 beam: the quantum

efficiencies measured at 180 nm were 0.15, 0.17, 0.18 and 0.21. The time evolution of the best photocathode

produced in 1994 was followed during 1995 at the test beam. Such ageing tests performed on the long time

storage of photocathodes indicated a small deterioration of the quantum efficiency, but still compatible with

the requirements of experiments.

Two of the freshly-produced photocathodes of size 25 x 80 cm? were mounted in the Threshold Imaging

Cherenkov (TIC) of the NA44 Collaboration. The earlier version of this detector used TMAE as the

photoconversion agent, implying a large conversion gap which severely limited the beam rate on target. The

use of solid photocathodes, resulting in a considerable reduction in the photo-active volume of the detector,

allowed running at very high beam rates. The solid photocathodes performed successfully in the 1995 ion run

period, and, to our knowledge, this was the first time in an experiment that particle identification had relied on

a CsI-based detector.

We were involved in the design and simulations of performance for the High Momentum Particle

Identification (HMPID) array in the ALICE experiment, where a CsI photocathode in a proximity focusing


RICH was retained as the baseline choice for a 12 m? detector coverage. A HMPID module of 1.7 m? was

designed and will be constructed at a reduced (2/3) size, to be tested under high track multiplicity conditions.

The development of the associated pad front-end electronics was pursued by producing the multi-chip version

of the DIGITPLEX, providing a multiplexed analogue read-out with zero suppression on chip.

RD27 - Study of First-Level Trigger Systems for General-Purpose LHC Experiments

Research and development project RD27 (Birmingham; CERN; Heidelberg; Linköping; MPI, Munich;

QMW, London; RAL; RHBNC, London; Rome; Stockholm; Wisconsin) is studying first-level trigger systems

for the general-purpose LHC experiments. Items under study are subtrigger processors based on calorimetry

(electrons, photons, jets and missing transverse energy) and muon detectors, and the central trigger processor.

Extensive tests of a demonstrator-prototype first-level muon trigger were conducted using electronics

developed in RD27, connected to a 50 x 50 cm? trigger tower with several Resistive Plate Chamber layers in

each of two orthogonal projections, with a layout similar to the one planned for ATLAS. The trigger system

was based on a programmable coincidence-matrix Application Specific Integrated Circuit (ASIC), designed in

RD27 and manufactured in a 0.5 um CMOS gate array. The ASICs were mounted in custom-made VME

modules which were connected together to form the demonstrator trigger system. Tests at the H8 beam

showed excellent real-time performance, with a total latency through two stages of coincidence logic of only

- 30 ns and with time stability - 2 ns, as required for ATLAS.

Substantial progress was also made on the demonstrator programme for first-level calorimeter triggers. A

new custom-made flash ADC system was used to digitize signals from an ATLAS prototype liquid-argon

calorimeter. The ADC data were fed into demonstrator-prototype bunch-crossing identification logic systems

which applied digital signal processing in real time at a rate of 40 MHz, passing to subsequent trigger-

processing logic only data corresponding to in-time signals. Two implementations of the bunch-crossing

identification logic were evaluated—one based on Field Programmable Gate Arrays (FPGAs) using which

several algorithms were evaluated, the other an ASIC implementation for a single algorithm. All the

algorithms studied used finite-impulse-response filters followed by peak finders.

Another aspect of the work on the calorimeter first-level trigger was studies of fast-input data links. With

- 8000 8-bit words of input data at a rate of 40 MHz, the triggers for the LHC experiments have to handle a

massive input data rate (>2500 Gbit/s). Furthermore, the input data links must be synchronous and have low

latency. Initial evaluations of a commercial solution are encouraging, but more extensive studies are required.

A custom solution is also being investigated and a demonstrator ASIC was designed in RD27 and submitted to

a manufacturer.

Several other ASIC evaluations are in progress. An example is a very high speed 8-input adder circuit,

designed within RD27 and implemented using a 0.6 um GaAs process. This device was tested at speeds well

in excess of 160 MHz, allowing four sets of data to be added during each 25 ns period.

A central trigger processor demonstrator is under development, based on FPGA circuits. The work on

developing the configuration data for the FPGAs is complete and the system is under construction.


RD28 - Gas Detectors Development (PPE-GDD)

The RD28 Collaboration consists of CERN; BINP, Novosibirsk; CRN-Strasbourg; CRPP/Carleton

University, Ottawa; DAPNIA-Saclay; INFN, Turin Univ.; FERMILAB; FPNT, Univ of Mining and

Metallurgy, Cracow; Univ. of Santiago de Compostela; IIHE, ULB-VUB, Brussels; NRCPS-Demokritos;

Institute of Physics of the Czech Academy of Sciences, Prague; Comenius University, Bratislava; Inst. of

Physics of the Slovak Academy of Sciences, Kosice; IPN-Lyon; Institute for Synchrotron Radiation, Aarhus;

ITEP-Moscow; JINR, Dubna; Univ. Coimbra; LN-INFN-Frascati; LN-INFN-Legnaro; LN-INFN-Gran Sasso;

LPI-Moscow; LPPE-Mons; MPI-Heildelberg; NIKHEF, Amsterdam; NPI-Moscow; University of Michigan;

Northwestern University; Birmingham University; Liverpool University; Manchester University; PHASE,

CRN-Strasbourg; RAL; SUNY, Stony Brook; Texas A&M University; TRIUMEF, Vancouver; UCL; Weizmann

Institute of Sciences, Rehovot.

In the framework of RD10 and RD28, the Gas Detectors Development group pursued basic investigation

of the manufacturing techniques and medium- and long-term operating characteristics of Micro-Strip Gas

Chambers (MSGC) in view of their planned use for the LHC trackers. In very close contact with industry,

several options for MSGC manufacturing were developed, with the goal of obtaining cheap and reliable

devices which can be mass produced. Using both chromium wet etching and gold lift-off technologies, defect-

free plates of active areas around 100 x 100 mm? were manufactured on thin glass and extensively tested. It

was confirmed that, in order to withstand the high rates and radiation levels at LHC, the devices must be built

on substrates having moderate resistivity (- 101* Cd/square); this can be obtained using electron-conducting

glass or, using a technology developed in collaboration with industry, by coating the glass before etching of

the manufactured chamber with a thin layer of CVD doped diamond (see Fig. RD28-1). The diamond coating

is cheap and impervious to external agents. Various improvements in the choice of gases and component

materials, achieved using results of the dedicated set-up in the RD10 laboratory, together with the

development of the resistive supports, proved that MSGC can withstand, at least in laboratory conditions, the

radiation doses anticipated for 10 years of continuous operation at LHC (Fig. RD28-2). Work is in progress to

demonstrate the same behaviour in more realistic running conditions, with the installation in a high-intensity

beam of a medium size set-up including two dozen fully-equipped MSGCs (in collaboration with the CMS

tracker group and the Physics Institute of Aachen University).

—

nm

: CERN-PPE-GDD Micro-Strip Gas Chamber ' 28.6.95 Chromium on Diamond-coated D-263

09}

0.8 |

Relative Ga

in

— u „H „

ui

o7| |

0.6}

| | 0.5 —

102 10° 10* 109 106 10° Rate (Hz mm“)

Fig. RD28-I: Rate capability (normalized gain vs. radiation flux) of a MSGC

manufactured on low resistivity diamond-coated glass. Maximum rates at LHC

are around 5 x 10° mm s!.


u

. u

5 | CHROMUMMSGCon | " CERN-PPE.GDD ] ® [ DIAMOND-COATED D-263 RD-28 14.9.95 | Z 18 u ® Dur in; Fr |

x } ii od ] 1 s r neun _

x a 4 ]

0.95 H--— 1 > t J

Ar-DME(50-50) | 03} V„=+530 V E

V4=-1000 V | + M = 1000 |

0.85 T Rate -10° mm? s-! “” Current Density - 9nAmm®

0.8 in ı a ,

0 20 40 60 80 100

Charge (mC cm")

Fig. RD28-2: Long-term behaviour (normalized gain vs. accumulated charge) of

a MSGC manufactured on diamond-coated glass. 100 mC/cm of charge

corresponds to 10 years of operation at LHC.

RD29 - A Mixed Analogue-Digital Radiation-Hard Technology for High Energy Physics Electronics: DMILL

During the period 1991-1995 the RD29 Collaboration (a consortium comprising CEA, Saclay; CEA-

LETI;, CEA, Bruyeres-le-Chatel; IN2P3/CPPM, Marseille; IN2P3/LAL, Orsay; Matra MHS) developed the

radiation-hard mixed analogue-digital technology DMILL for the production of electronic circuits for civil

and military applications. The features of this technology were adapted to fit the severe requirements of high

energy physics experiments.

DMILL uses an SOI substrate and integrates monolithically radiation-hard analogue-digital CMOS

(0.8 um), PJFETs (1.2 um) and NPN bipolar transistors. CMOS and bipolar transistors, in addition to their

radiation-hard properties, have electrical characteristics similar to those of standard unhardened BICMOS

technologies. These components were chosen to enable the design of both analogue and digital fast radiation-

hard circuits on the same chip. JFET transistors permit the design of low-noise very radiation-hard circuits for

TOOM- or cryogenic-temperature operation.

The typical characteristics obtained with individual transistors or with different mixed analogue-digital

circuits integrating up to more than 1 000 000 transistors showed that the DMILL technology satisfies the

various HEP circuit requirements, in terms of radiation-hardness (>10 Mrad and >10!* neutrons/cm?) and in

terms of dynamic electrical performance, noise, power consumption and integration density. A 16-bit

microprocessor (29101 type) developed in DMILL technology for non-HEP applications demonstrated a

radiation-hardness higher than 350 Mrad (SiOJ).

To make possible the development of prototype circuits dedicated to ATLAS or CMS by laboratories

involved in LHC experiments, a first MPC (Multi Project Chip, i.e. a batch of wafers processed using a reticle

containing different circuits) was organized in 1994 with DMILL technology. The production of three other


MPCs was organized in 1995 and that of three new MPCs will be organized in 1996 to allow laboratories to

carry out their work with DMILL until it is commercially available.

The stabilization of the DMILL process was completed at the beginning of 1995 within LETI (Grenoble,

France), which is the microelectronics development laboratory of the CEA. In September 1995, TEMIC/

Matra-MHS, a subsidiary of the French Matra-Hachette Group and the German Daimler-Benz Group, signed

a licensing agreement with the CEA for the transfer of DMILL to its 6" silicon foundry at Nantes (France).

The industrial transfer is currently in progress and will be completed by March 1997. The DMILL process will

then be qualified by MHS for manufacturing mixed analogue-digital circuits requiring a radiation hardness up

to 10 Mrad (SiO,) and 101* neutrons/cm?. DMILL will be commercialized, starting in 1997, for the

development of prototype circuits processed using MPCs or for the high-volume production of final circuits,

in accordance with the schedule of development of the LHC detectors.

RD31 - A High-Performance Data-Driven Event-Building Architecture based on an Asynchronous Self-Routing Packet-Switching Network

The RD31 project is a collaboration between Alcatel Bell Telephone; Saclay; CERN; Hewlett Packard;

Uppsala Univ.; KEK; MIT; and Royal Inst. Tech., Stockholm. The collaboration is studying the application of

large-scale data switches to construct parallel event builders for high-rate experiments. Optimized custom-

designed switching networks and industrial switch fabrics are under evaluation. Asynchronous Transfer Mode

(ATM) switches developed for the telecommunications and computer industries now appear promising

candidates.

ATM-VME interface modules and traffic generators with special features for event building were

constructed and interconnected with a commercial ATM switch designed for telecommunication. The software

protocols for event building were implemented. The performance of this small demonstrator can be measured

under various traffic patterns and intensities. Commercial interfaces are under test as well as alternate switch

technologies. The feasibility of various event-building strategies (e.g. ‘push’ vs. ‘pull’) is under investigation.

RD32 - Development of a Time Projection Chamber with High Two-Track Resolution Capability for Experiments at Heavy-Ion Colliders

The RD32 Collaboration (CERN; GSI, Darmstadt; IKF, Frankfurt; MPI, Munich; Nucl. Inst. Cracow;

LBL; Brookhaven Nat. Lab.; Utrecht Univ.) is developing a Time Projection Chamber (TPC) with high

double-track resolution. The track resolution is determined by the gas properties like the drift velocity,

transverse and longitudinal diffusion constants, the geometry of the read-out chamber and the front-end

_ electronics.

A TPC for tracking and particle identification operating in a high track-density environment needs front-

end electronics with extremely powerful tail compensation in order to avoid baseline shifts which would be

difficult to correct. Tail suppression to better than 0.1% of peak pulse height after about 1 us is mandatory for

occupation densities to be expected (e.g. at the ALICE experiment). A combined amplifying/shaping circuit

was developed to achieve this goal. The circuit uses a translinear input stage with good high-frequency

response followed by an integrating/differentiating stage to cut off the low frequency domain and to obtain the


necessary pulse shaping. Pulse width can be adjusted in a subsequent current-mode integration stage. The

circuit is gateable in order to use the gate-cycle of the TPC itself for effective power reduction. The ungated

power consumption is 4mW per channel for a 10 bit dynamic range. A first VLSI implementation of the

circuit was obtained using HARRIS radiation-resistant UHF3C bipolar technology. On-detector tests showed

that the required pulse-shape performance can be reached.

Work on a TPC read-out system based on the Micro-Strip Gas Chamber (MSGC) technique continued. A

TPC set-up with a 50x 50 mm? glass plate and MSGC structure was produced. Two pad structures were

investigated: (1) reverse pads evaporated on the side of the glass and (2) pads on a PC board insulated by a

Capton foil. With both methods more than 50% of the anode signal was induced on the pads, which is

sufficient for a TPC. The width (r.m.s) of the pad response function as a function of the glass thickness is

shown in Fig. RD32-1. For special applications, TPC read-out chambers employing this technique seemed in

principle to be possible with a r.m.s width of <1 mm for the pad-response function. Long-term stability

investigations have to follow.

2

18, 16} 14

12!

u: 08 | 06} 0.4 [

02}

Gy/mm

0 0 025 05 075 1 1.25 15 175 2 225 25

Thickness of the glass/mm

Fig. RD32-1: The width (r.m.s,) of the pad-response function versus the glass

thickness between anode and pad for MSGCs. Open circles, triangles, and

squares represent Ar/CO, (90/10) structure (1); Ar/CH, (90/10) structure (1);

and Ar/CH, (90/10) structure (2), respectively.

RD34 - Developments for a Scintillating-Tile Sampling Hadron Calorimeter with ‘Longitudinal’ Tile Configuration

After the positive results of 1993 and 1994 the RD34 Collaboration (Argonne National Lab.; Barcelona

Autonomous Univ.; Inst. for Atomic Phys., Bucharest; CERN; Univ. of Chicago; Clermont-Ferrand Univ.;

Academy of Science of the Czech Republic; Dubna JINR; Univ. of Illinois; LIP, Lisbon; Michigan State Univ.;

Pisa Univ.; Charles Univ., Prague; Serpukhov IHEP, Protvino; Univ. Fed. Rio de Janeiro; Stockholm Univ.;

IFIC, Valencia; Univ. of Texas at Arlington; Yerevan Phys. Inst.) pursued additional R&D in the field of hadron

sampling calorimetry. The hadron calorimeter proposed by the ATLAS experiment at LHC uses steel as

absorber and scintillating tiles read out by wavelength-shifting fibres. The tiles are placed in the plane


perpendicular to the colliding beams, allowing simple, highly modular and economical assembly. In the

ATLAS design this calorimeter will be placed behind a thick electromagnetic section, based on LAr

technology (the Accordion project). The overall structure will be cylindrical with an inner radius of 228 cm, an

outer radius of 423 cm and a total length of 1220 cm, for a total weight of about 2600 tons.

In the first years of the project a five-module prototype calorimeter was constructed and exposed to high-

energy pion, electron and muon beams in the standalone mode (no electromagnetic section in front) at the

SPS/CERN. Besides confirming the expectations of good response uniformity and energy resolution, the data

showed that excellent signal linearity could be obtained by a simple sampling correction method.

The pion energy resolution was studied in the energy range 20-300 GeV and at angles of incidence

from 0° to 45°. The energy spectra are symmetric at all energies and display small or no tails on the high-

energy side. For raw data, a resolution of O/E=47%NE + 2.2% is obtained at a 20° angle of incidence.

This result was improved by using a simple depth correction weight for the four depths. The resolution

becomes o/E = 45% NE + 1.3%. The results are in reasonably good agreement with detailed simulations.

The uniformity was studied with pions of 40 and 80 GeV, at a 10° angle of incidence. A 60 cm scan across

the front calorimeter face shows that the response is uniform to within 0.9%. The e/n ratio was determined to

lie between 1.1 and 1.2 over the energy range studied. The pion signal linearity ıs fully recovered after the

depth correction; the r.m.s. deviation is about 1% in the energy range studied. The calorimeter response to

muons was investigated using 300 GeV muons at various incident angles. Muons leave a clean signal in the

prototype sectors equivalent to an energy of about 2.8 GeV, well above experimental noise sources. These

results confirmed the validity of this technique and led ATLAS to adopt the tile calorimeter concept for the

barrel hadronic calorimeter (n]| < 1.6).

The attempt to understand the hybrid environment, where the tile calorimeter is preceded by 1.2 interaction

lengths of LAr Accordion EM calorimeter, was the main motivation for extending the project through 1994

and 1995. A combined run took place at the end of 1994. Results show good agreement with the stand-alone

performance at high energies and slightly worse agreement at lower energies due to experimental problems of

the set-up. A typical, clean line-shape obtained in the combined run for 300 GeV pions is shown in

Fig. RD34-1. A resolution of 4.0% is obtained. A new combined run with emphasis given to low energies is

scheduled for April 1996.

Detailed component R&D efforts were carried out in order to further improve the calorimeter performance.

In the 1995 tests, the central tile calorimeter sector showed the best performance in terms of light yield and

light uniformity due to the use of double-clad fibres and an improvement if the tile quality and geometry of the

tile/fibre coupling. The light yield increased from 24 p.e./GeV in 1993 to 64 p.e./GeV in 1995, as can be seen

in Fig. RD34—2.

Important progress was also made in the overall engineering of such a large device, both from the

mechanical and the electronics points of view, aiming in 1996 for the construction of a module O of the

ATLAS detector, before the final production phase.


Most of the results mentioned above were published [Nucl. Instr. Methods A349 (1994) 384] and several

diploma theses on this subject were completed in the collaborating institutions. At present there are three

papers in preparation. One paper reviews the hadronic performance of the tile hadron calorimeter when tested

together with the LAr Accordion EM calorimeter. The response of the tile calorimeter to muons is the subject

of the other two papers.

450 I 300 GeV x 400 : o/E=4.0% Ev

ents

350 |

300 I

250 |

200 |

150 |

5

50 200 250 30 30 400 450 Energy (GeV)

Fig. RD34-1: Combined LAr Accordion EM and tile hadron calorimeter

response to 300 GeV pions at an incidence angle of 11°.

> 0,

Io 9 s3 sa = nt H re N N SEHE RER ER

zu 9040 40 F er

30 F nnagernann Bon. ocean. PL

20 F F = 1995(64+3.5 p.e./GeV)

10 E o 1994(48+3.8 p.e./GeV) e 1993(24 p.e./GeV)

0 Do bar

0246 8 410 12 14 16 18 20 Tile number

Fig. RD34-2: Number of photoelectrons per GeV per cell as a function of the tile

number. Numbers are given for the tile calorimeter prototypes built in the years

1993, 1994 and 1995.


RD36 — A Shashlik + Preshower Detector as Electromagnetic Calorimeter for LHC

The aim of the RD36 Collaboration (CERN; Tata Inst., Bombay; RAL; Dubna JINR; Univ. of Ioannina:

LIP, Lisbon; IC, London; INR/ITEP, Moscow; Ecole Polytechnique, Palaiseau; IHEP, Protvino; Univ. of

California, San Diego; Univ. of Split; Texas Tech. Univ.; Brunel Univ.) is to develop a lead scintillator

sampling calorimeter read by wavelength-shifting fibres (Shashlik calorimeter) connected to a silicon strip

preshower, and to study their possible performance and implementation for LHC experiments.

From built prototypes, light yields in excess of 20 photons per MeV were obtained. The collaboration

performed measurements of the energy and position resolutions of various prototypes with or without a

magnetic field and with or without preshower. The energy resolution measured on bare towers from our

last 6 x 6 matrix prototype (Fig. RD36-1) is characterized by a stochastic term of 8.1%/NE, a noise term of

0.330/E and a constant term of 0.5% (E in GeV).

Shashlik alone (3 deg. tt)

# o Tower-15

0.04 5 o Tower-16 A Tower-21

04 "> Tower-22

0.03 +

wo o/E = 8.1% NE © 330 MeV/E © 0.5% o

0.02 +

0.01 F

0 Ir N BE A ı i L 094 I

0 50 100 150

Epeam (GeV)

Fig. RD36-1: Energy resolution obtained for four Shashlik towers exposed to

high-energy electrons.

The reproducibility of the tower performance and the uniformity of the calorimeter response were studied

on a large (25 x 25 cm? cross-section) prototype. A mean dispersion of less than 1% was achieved.

We also developed and studied multi-bundle Shashlik towers. This technique allows larger towers to be

built (6 x 6 cm? are foreseen for the CMS barrel), read out with 2 to 4 WLS bundles of fibres, giving (due to

the crosstalk between channels) redundancy in the read-out, and improvement in the shower position

resolution and angular resolution without losing any precision in the energy resolution. Several of such towers

were studied in a high-energy electron beam in 1995 confirming the previously obtained performance.

Another goal of RD36 is to study the preshower detector which has to be placed in front of the calorimeter.

The preshower consists of several layers of lead radiators followed by silicon strip detectors. Together with the

position measurement in the calorimeter, the preshower allows a measurement of the shower direction. New

preamplifiers, analogue memories and chips for the silicon strip read-out were produced and tested at CERN

by an ECP MIC group. The shower angular resolution is better than 70 mrad/VE. The energy resolution of the


bare calorimeter is fully recovered after correction for the energy lost in the lead radiators, using the measured

charge in the silicon detectors (Fig. RD36-2).

Several towers built out of radiation-hard scintillator and WLS fibres were irradiated in 1995 with

500 MeV electrons produced at LIL, and gave encouraging results.

Shashlik + Preshower {3 deg. it)

+ o Tower-15

0.04 7 - Tower-16 A Tower-21

| 5 Tower-22

0.03 r

Au o/E = 8,9% NE ® 320 MeV/E ® 0.5% 0.02}

0.01

0 [ ı L ı ı j ı ı L L l L ı y | ı

0 50 100 150

Epaam (GeV)

Fig. RD36-2: Energy resolution obtained for Shashlik towers exposed to high-

energy electrons with two planes of silicon strip detectors in front of the towers.

First and second silicon planes had a 2X, and 1X, lead absorber in front,

respectivel,y.

RD37 - Very Forward Hadron Calorimetry at the LHC using Parallel Plate Chambers

The main goal of the RD37 Collaboration (CERN; CIEMAT, Madrid; INFN, Univ. Florence; ITEP,

Moscow; ATOMKI, Debrecen; KFKI-RMKI, Budapest; PNPI, St. Petersburg; IHEP, Protvino) is the

application of the Parallel Plate Chamber (PPC) technique for low-angle calorimetry in LHC experiments.

The main results in 1995 were the following:

— Spark probability measurements in the full gain (G) range (from 10? to 10°) [RD37 TN/92-12] for two

different gases: 3.1 x 10?’ G*°? for CO,, and 4.2 x 102° G*?? for CF4/CO, (80/20).

— Radiation hardness. The irradiation of PPCs with gammas and neutrons was pursued, monitoring the

current. For gammas the current was still constant after 500 Mrad (December 95). Irradiation will

continue until it reaches the Grad level. For neutrons the current level of irradiation is

0.5 x 101° neutrons per cm”. A small increase of the current was observed due to the activation of the

container (made of stainless steel) of the PPC cells. Irradiation will continue until it reaches the level of

1.5 x 10!© neutrons per cm?. Preliminary results can be found in RD37 TN/94-3.


— Calorimetry studies with an electron test beam. A small prototype module consisting of 13 PPC planes

(3x3 PPCs per plane, 117 read-out channels in all), interleaved with 30 mm iron plates (22 X,) was

tested [RD37 TN/95-11] using electrons of 5-100 GeV/c momentum with various high voltages and

two gases, CO, and CF4/CO; (80/20), at atmospheric pressure. The collected charge was measured as a

function of the high voltage and of the electron energy. The energy resolution was also measured,

giving I90%NE for the gas mixture. Our Monte Carlo reproduces the results very well.

— Calorimetry studies with a hadron test beam. A big prototype (about 2 tons) consisting of 15 PPC

planes (8x 8 PPCs per plane, 960 read-out channels in all) interleaved with iron plates of variable

dimensions (6.8 interaction lengths in all) was tested using muons, electrons, pions and protons of

energies varying from 50 to 375 GeV/c, with various high voltages and using a CF,/CO, (80/20) gas

mixture at atmospheric pressure. The collected charge was measured as a function of the high voltage

and of the particle’s energy. The hadron energy resolution was also measured: 190%NE with a constant

term of 13%. Once again our Monte Carlo reproduces the experimental data very well. This agreement

allows predictions to be made for a full-size Very Forward Calorimeter.

The RD37 Collaboration will finish its hardware activity in April 1996, with a test beam using

12 interaction lengths (the full length for this type of calorimeter) and 20 PPC planes (1280 PPCs, one third of

the nominal packing fraction, but with the same number of read-out channels). The software (data analysis)

work will continue until the end of the year.

RD38 — A Study of Generic Control Systems for Large-Scale LHC Experiments (CICERO) |

The RD38 Collaboration consists of CERN; BARC, Bombay; Ivo International, Vantaa; KFKI, Budapest;

OBLOG, Lisbon; SEFT, Helsinki; SPACEBEL, Brussels; SUPRA, Budapest; VALMET, Tampere; VTT, Onlu;

and UWE, Bristol.

Modern high-energy physics experiments and accelerators require sophisticated control systems to ensure

their safe operation and to optimize their performance. Due to their complexity and to the large number of

sensors needed for these purposes, these control systems turn out to be difficult and costly to maintain with

present technology. The situation will seriously worsen with the LHC era. The R&D departments of various

industrial companies are directly concerned with similar difficulties in power plants and complex automated

systems. We combined our efforts to study the various aspects of this problem. The main building blocks of a

generic control information system were outlined and constructed. A software backbone called Cortex

providing the integrating capabilities and the extended communication support for the integration of

heterogeneous legacy control products was developed. To support the long life-cycle of these large projects,

the software backbone relies on CORBA, the powerful emerging standard proposed by all the major computer

manufacturers. In addition, CICERO provides a series of common components, to be used as templates for the

construction of specific CORBA compliant control services such as Archiver/Retriever, Finite State machines

and GUI. A prototype was built as a first step towards our main goal to provide technical solutions which could

later be the major components of a basic turnkey system for medium- to large-scale HEP experiments and

accelerators.


Phase I was completed in March 95, its main purpose being to demonstrate the feasibility of integrating

heterogeneous control software to build a distributed control system. A prototype of a muon and gas control

system was built to illustrate the key concepts proposed by the CICERO Collaboration. The 1994 DRDC

Report is available in HTML and PostScript formats.

The main feature of this prototype was the integration of commercial and home grown control software

into a distributed environment, with fully CORBA v1.0 compliant software backbone. The prototype was

presented in March 95, and the first year of a second phase of the project was approved by the CERN

management. A pilot project is now underway, divided into two stages. A first stage will provide a re-

engineered version of the muon control system to be installed in L3 during the 1995-1996 shutdown. A

second stage is under study and is pending approval. It intends to provide a re-engineered version of the

central control system of the experiment based on the ideas which have been validated in the prototyping

phase. This will involve construction of a full scale control system based on commercial software which is

fully CORBA compliant; basic operation software components such as Archiver/Retriever, Logger, GUI, and

Finite State Machine components will be included.

RD39 — Superconducting Microstrip Detectors

The RD39 Collaboration (CERN; Helsinki Univ. of Tech.; VTT Tech. Research Centre of Finland)

addresses the feasibility of superconducting-strip tracking devices for applications in high-intensity beams

and experiments at LHC. These devices feature radiation hardness two orders of magnitude higher

than conventional silicon strip detectors, spatial resolution limited only by lithographic techniques (typically

0.1-2 um), an intrinsic signal rise-time of 2 ps, and signal transport over large distances without losses.

An NbN sputtering facility was set up in VTT and test films showed good characteristics. The design of the

first test-circuit series was completed and masks were produced using a laser interferometer. Circuit

simulation, using a computer program which includes superconducting circuit elements, showed that the

signal shape, in particular the sharp rise-time, is well preserved in the circuit up to the coaxial line transition.

Processing of the first wafers was completed at the beginning of 1995 and the characterization of the films

and strips in the temperature range of 2-15 K showed a maximum critical current density of 3 x 10° A/cm/,

lower than was expected from the test films with simpler patterning. Tests at microwave frequencies and with

fast pulses validated the basic design features of the circuits. A new series of wafers is being processed under

cleaner conditions, and using better techniques to avoid possible weak spots.

A new cryogenic probe card was designed to allow ultrasonic wire bonding, instead of mechanical

pressing of contacts, between the test chips and the sample jig in the RD39 cryostat. Laboratory and beam

tests with minimum-ionizing particles are in progress.

RD40 - Development of Quartz Fibre Calorimetry

The RD40 Collaboration (CERN; CRN, Strasbourg; INFN, Univ. Bologna; INFN, Frascati; INFN, Univ.

Turin; FSU, Tallahassee; ITEP, Moscow; PHASE, Strasbourg; INFN, Pavia Univ.; INFN, Pisa Univ.; Cornell

Univ.) is developing a new calorimetry technique which involves embedding quartz fibres in a dense absorber.


The shower particles are detected through the Cherenkov light they create in the fibres. This technique is in use

as a0° calorimeter in NA50, as an EM calorimeter to measure the impact parameter in NA52, in a polarimeter

at SLAC and will be used for the Very Forward Calorimeters of CMS and to measure the luminosity at RHIC

(BNL). RD40 is studying the linearity, the resolution and the transverse shower size for EM and hadronic

showers.

— The radiation resistance of fibres is being studied. Fibres whose preform history is known have been

drawn from special HERAEUS preforms with the best silica stochiometry, and will soon be irradiated

at LIL. The apparatus, based on the use of a reflection grating, is ready to measure the resistance to

radiation with respect to Cherenkov wavelength.

— Electromagnetic calorimetry studies are complete: nine EM prototypes were tested with lead and

copper as absorbers along with three types of quartz fibres and also transparent PMMA fibres. The

results are summarized in the doctoral thesis of Mark Lundin, completed last June at the Universite

Louis Pasteur in Strasbourg. All of the previous results are confirmed, concerning the excellent

linearity, the amount of light produced, the resolution (0% stochastic term for 45° fibres orientation)

and the very small shower sizes. These studies were completed by the in-depth analysis of the sampling

fluctuations which allows the prediction of any quartz fibre EM-calorimeter behaviour without Monte

Carlo simulations.

— Hadronic calorimetry. As the cheap transparent plastic fibres produce good results for EM showers,

they were used in two hadronic prototypes, one with fibres at 0° and one at 45°.

The 0° prototype is made of 4 pieces, each 200 cm long with a 10 x 10 cm? transverse section set side-by-

side to make a 20 x 20 cm? transverse dimension. The fibres are 1 mm in diameter with a 4/1 filling ratio in

lead. The prototype is read by four 3-inch phototubes.

The 45° prototype is made of 9 blocks, each about 20 cm long. Their transverse section is 5X 5 cm? at the

beginning and 60 x 60 cm? at the end. The fibres are 0.5 mm in diameter with a 1/10 filling ratio in lead. The

last 5 modules (40% of the energy) are there only to contain the energy and do not contribute to the position

determination of the shower. The first 4 modules have the fibres laterally separated in 5 bands: the 3 central

bands are one sigma of the local shower width and the 2 lateral bands are 5 sigma. Each layer is tilted laterally

+15°, then -15°, then +15°, etc. This allows precise shower-position and shower-width determination from the

produced u-v coordinates.

The two prototypes contain more than 95% of the showers. They were tested in June 1995 at the SPS. The

0° data are good and reproduce our Monte Carlo predictions. The position information in the 45° prototype

cannot be used due to strong crosstalk between pixels in the photodetectors used to read the central bands.

After correction, this measurement will be repeated in April 1996.

RD42 - Development of Diamond Detectors for the LHC

RD42 (Bristol Univ.; CPPM, Marseille; CERN; LEPSI, Strasbourg; Livermore; MPI, Heidelberg; Ohio

State Univ.; INFN, Pavia Univ.; Rutgers Univ.; Vienna) continued to develop CVD diamond material to use as

radiation-hard substrate material for solid-state trackers in the high-radiation environment of LHC

experiments. The collaboration grew by four institutes in the last year. Three of the four new groups specialize


in materials science, adding considerable expertise to help us understand the properties of the CVD diamond

material we are using.

During the past year we tested the first 50 um pitch diamond trackers. These detectors show signal-to-

noise ratios in excess of 30 to 1 and signals nearing 4000 electrons (Fig. RD42-1). This represents a factor of

two improvement over the year and leaves us only a factor of two away from our goal of 8000 electron signals.

A position resolution of 12 um (Fig. RD42-2) was also attained. We are studying in detail the charge

collection properties between strips and near the ends of strips to better understand the signal production

mechanisms. This prepares us for the next step in diamond tracker development: the study of pixel devices.

During 1995 we entered into a successful collaboration with the DeBeers Industrial Diamond Division in the

UK who are now a second viable supplier of detector-grade diamond material.

0 50 100 150 200 250 300

Charge (ADC counts)

Fig. RD42-1: The charged-particle signal distribution obtained for a tracker

tested in September 1995. The average signal observed is 3800 electrons.

€———ii««,ee«eee.:.e.ö:.,eöeheaeaeöö«eö;.«eese.6.6«.«ä«ä«äöe«”«ss-=——

>

-100 -50 0 50 100

Xnit — Xırack (IM)

Fig. RD42-2: The position resolution of a tracker with 50 um read-out pitch. A

resolution of 12 um is observed.


The main attraction of diamond-based sensors for the LHC is that they are radiation hard. Our study of

CVD material exposed to pions [CERN-PPE/95-173] was submitted for publication in Nuclear Instruments

and Methods. In 1995 we increased the pion dose to 5 x 10!* cm? to continue our studies. We also carried out

extensive studies with neutrons. We exposed samples to fluences in excess of 101° cm”?. For doses up to

101° cm”? we see changes in signal pulse height of less than 10%. As this represents the lifetime dose at a

radius of only 10 cm in an LHC collider detector we are pursuing these studies to higher fluences while trying

to better understand the effects which contribute to the changes in pulse height (e.g. damage to the diamond

bulk versus damage to the metal read-out electrodes) and thus produce detectors which can survive for the

lifetime of the LHC at smaller radii.

RD43 - Research and Development of a Hadron Calorimeter for High Magnetic Fields

The goal of the RD43 experiment (Iowa State Univ., Ames; Univ. of Michigan; Beijing HEP Inst.; Virginia

Poly./Univ., Blacksburg; Bombay TIFR; Northeastern Univ.; CERN; Dubna JINR; Yerevan Phys. Inst.;

Fermilab; Florida State Univ.; Univ. of Iowa; KSU/KhFTVISC, Kharkov; Purdue Univ., Lafayette; Maryland

Univ.; Michigan State Univ.; Univ. of Minnesota; BRPAPM/NCPHEP, Minsk; INR/ITEP, Moscow; Univ. of

Notre Dame; Princeton Univ.; Univ. of Rochester; Serpukhov IHEP; Sofia INRNE/Univ.; Tashkent INP;

Tbilisi State Univ.) is to perform R&D for a compact hadron calorimeter which can operate in magnetic fields

up to 4 TT. The specific application of this R&D is found in the CMS experiment.

Extensive beam tests were carried out in 1995 on prototypes simulating the barrel and end-cap

configurations of the calorimeters in CMS.

The barrel configuration consisted of lead tungstate crystals followed by nineteen Cu plates with

thicknesses of 3 or 6cm. These plates sandwiched 4 mm thick scintillator plates embedded with 1 mm

diameter plastic wavelength-shifting fibres. The light from the crystals was detected by Si avalanche

photodiodes. The solenoid coil was approximated by Al and Fe plates, with a total thickness of about 1.4

absorption lengths. The coil mock-up was followed by a tail catcher consisting of four Cu plates of a thickness

of 8 cm. This array, with individual scintillator read-out, allowed simultaneous recording of data on a variety

of possible absorber/sampling arrangements. Data were taken with pion energies as high as 375 GeV. It was

found that the tail catcher is necessary in order to decrease the non-Gaussian tails in the energy distributions. It

was also found that an increased weighting of the signal of the last scintillator before the coil decreases the

tails. This can be accomplished by adjusting the thickness of the scintillator plate and/or increasing the number

of embedded WLS fibres.

The end-cap configuration consisted of a silicon preshower detector (3 X, of lead followed by two planes

of Si detectors with 2 mm pitch Si strips), followed by lead tungstate crystals, nine 5 cm thick copper plates

and eleven 10 cm thick copper plates. These plates sandwiched 4 mm thick scintillator plates embedded with

l mm diameter plastic wavelength-shifting fibres. The light from the cerystals was detected by vacuum

phototetrodes. This test was carried out in a field of 3 T oriented in the direction of the incident beam. The

energy distributions were found to be Gaussian and the energy resolution of 300 GeV charged pions was

measured to be = 7%.


The R&D programme accomplished its goals and has been terminated. Work is now going on in the

context of CMS to construct full-size prototypes.

RD44 - GEANT4

GEANT4 (RD44) is a worldwide collaboration of scientists (II Phys. Inst., Aachen TH; NIKHEE,

Amsterdam; LAPP, Annecy; IBM, Austin; INFN, Bari Univ.; Bath University; Bombay TIFR; Budapest Res.

Inst. of Physics (KFKI); CALTECH; Cambridge Univ.; CERN; Fukui Univ.; DESY, Hamburg; Helsinki Univ.

of Technology; Helsinki Univ.; Inst. of Tech., Hiroshima; KEK, Japan; Kyoto Univ.; Lawrence Berdeley Lab.;

Lawrence Livermore Nat. Lab.; Cray Systems, London; Manchester Univ.; Moscow Lebedev Phys. Inst.;

Naruto Univ. of Education, LAL, Orsay; INFN, Padua Univ.; KLA Instruments, San Jose; Sofia Univ.;

DAPNIA, Saclay; Serpukhov IHEP; Intern. Christian Univ. Tokyo; Tokyo Metropolitan Univ.;, TRIUMF,

Vancouver; Univ. of B.C., Vancouver) aiming to create a detector simulation software toolkit necessary for the

next generation of HEP experiments.

There are also a variety of requirements from heavy-ion physics, CP-violation physics, cosmic-ray

physics, medical applications and space science applications. In order to meet such requirements, a large

degree of functionality and flexibility has to be provided.

GEANTA4 exploits Object Oriented Technology to achieve these goals. The most relevant Object Oriented

methodologies were studied and a large number of tools and libraries were investigated and evaluated. Object

Oriented Analysis and Design (OOA&D) were performed for the global simulation framework. The User

Requirement Document, the OO class diagrams, the OO interaction diagrams and the OO class specifications

were delivered.

A prototype was developed, including sufficient functionality in terms of the geometry, event management,

tracking and muon physics to be compared with GEANT3. The results of the benchmarks performed show

that time performance is better than in GEANT3 for all the cases evaluated. Accuracy of the tracking and

physics results was investigated and found to be at least as good as, or better than, the corresponding results in

GEANT3.

RD45 - Object Persistency

The LCRB project RD45 (Argonne Nat. Lab.; Birmingham Univ.; Bombay TIFR; CERN; Cornell Univ.;

Cracow Inst. Nucl. Phys.; GSI, Darmstadt; Freiburg Univ.; INFN, Naples Univ.; INFN, Rome Univ. I; ETH,

Zurich) was approved to solve the problem of LHC event data VO. The goals of this project are to find

solutions to the problems of handling Persistent Objects for LHC era events—essentially the management of

LHC event data. The focus has been on standards, and a widely accepted architecture, based on the use of

commercial standards-conforming Object Databases coupled transparently to Mass Storage Systems, was

developed.


RD46 — High-Resolution Tracking Devices Based on Capillaries Filled with Liquid Scintillator

The objective of the RD46 Collaboration (NIKHEF, Amsterdam; Humboldt Univ., Berlin; IIHE/ULB-

VUB, Brussels; JINR Dubna; CERN; Technion, Haifa; Westf. Wilhelms Univ., Munster; Univ. Federico IV

INFN, Naples; Univ. La Sapienza/INFN, Rome; Serpukhov IHEP) is to develop high-resolution tracking

devices based on thin glass capillary arrays filled with liquid scintillator and highly integrated read-out based

on the use of Electron Bombarded CCD (EBCCD) and Vacuum Image Pipeline (VIP). The experimental

innovations include, in particular: improvement of the technique of capillary bundles production, and the

development of a small detector prototype composed of planar layers 1-3 mm thick built with 20 um diameter

capillaries; development of EBCCD tubes (Fig. RD46-1a) and related low-noise read-out electronics, and the

construction of detector prototypes with optoelectronic chains based on this new technique; and development

of an image-delay technique with VIPs (Fig. RD46-1b) for very high-rate applications.

(a) Photocathode

w....

nn dell

I N |

I III

N N Ir. [777

* ° Ser N N 9 r LITER

Fibre optic -—\ A\P j CCD Ep AZLZanN Ra z 2

window a N ANY DRS

Focusing electrodes

VIP SCHEME

(b) PHOTOCATHODE PHOSPHOR

2" “ ii s >

INCOMING 8 '2_ . . .o_° ö_ = TRIGGERED

ir = EBR-GE » ZEROELECTRICFIELD » REFLECTION » GE» SE | ge 29-09» SECTION ° SECTON »- WO-EO ES

auch e . .e on’ in =

8 . eo . . . =

Fig. RD46-1: Schematic diagrams of (a) an Electron Bombarded CCD (EBCCD)

and (b) a Vacuum Image Pipeline (VIP).

The RD46 proposal was prepared and the collaboration formed in 1995. A large size bundle target with

conventional read-out was placed in a muon/neutrino beam and the tracking performance was studied. Typical

neutrino interactions are depicted in Fig. RD46-2. A first prototype with EBCCD read-out was prepared and

tested with cosmic rays. VIPs with 0.4-1.5 us delay were developed and tested in the laboratory. Simulation

and design studies were also performed to integrate the various devices into detectors with possible LHC B-

physics and neutrino physics applications.


EI

E

20 H- -. . “ en.

Bee _ if .

. SF ne

10 u uf a nu , . “ . . _ Law

F no BEE Pre ehei “ BA | . . .

5 |.. u,

Q lu: li: is bu En

0 5 10 15 20 25 30

(mm)

Fig. RD46-2: A neutrino interaction recorded during measurements at the SPS

neutrino beam.

Technical Developments

Engineering and Construction Group (EC)

CHORUS: The group participated in the reinstallation of the four planes of 800 kg of nuclear emulsion

after the 1994/95 annual shutdown, and in regular exchanges of some specific emulsion sheets. Special

attention was paid to the slow controls of the detector, the operation of the hexagonal magnet, and the gas

system. After the run period the hexagonal magnet was thoroughly checked for signs of material fatigue and

modified to reduce a small axial stray field.

Support for the new arrangement and axial extension of the double-sided silicon microstrip detector of

OPAL continued. The detector will be equipped with additional chips of microstrips and will be ready for re-

installation in OPAL during the 1995/96 shutdown.

Support for the LHC Collaborations increased. For CMS, it continued finite element calculations to

determine stress and deformation of the magnet structure in order to further optimize its design. It also assisted

with the magnet assembly and detector integration. The ‘Ferris Wheel’, a large handling device for the

assembly of the magnet rings, was designed. Furthermore, design work started on a reference system made

from ZERODUR for the muon chamber alignment.

For ATLAS, the group is in charge of the layout and design of the central rail and support structure and of

the displacement system for various detectors, of the design of the forward shielding, and of the layout and

integration of the muon detection system in the barrel magnet. A large effort went into the preparation of series

production of the first long pressurized drift tubes of the muon chambers and into the production of a first real

module of both the electromagnetic (accordion) and the hadronic (tile) calorimeter. Work on the 1:10 scale

model of the complete detector continued.


Part of the group prepared and assisted in field measurements of the magnets used in experiments. For

NA49 particular support was given for the precision measurement of the two vertex magnets and their stray

field at the main TPC. Field maps were calculated with the TOSCA program to optimize measurement grids

for several magnets and to help with design and layout studies of the ATLAS tile calorimeter. A few magnets

had to be repaired.

The group provided mechanical help for installing the laser calibration system of NA49. The ISOLDE

facility received mechanical help for installing the second Faraday cage, and design support for different

detecteor displacement systems. The RFMASS experiment at this facility received support for the layout and

design of an r.f. modulator.

Detector Construction Group (DC)

The main activities of the DC Group were as follows:

NA 48:

— Follow-up of the cold window construction in industry.

— Reception and testing of the windows at low temperature.

— Reception and testing of the beam pipe at low temperature.

— Design and fabrication of two cold-boxes.

— Design and fabrication of the Krypton condenser.

NOMAD: Installation of the Veto Counters and the Hadronic Calorimeter.

CMS: Design studies and elaboration of specific details of the Iron Barrel Yoke.

ATLAS: Design studies.

PPE WORKSHOPS: Substantial help was given to groups in the Research Sector, to the LEP2 and LHC

programmes, as well as to visitor teams with the fabrication of mechanical components, a total of

- 48 500 working hours.

Technical Assistance Group 1 (TAl)

ATLAS Transition Radiation Tracker: The forward TRT prototype was finished. Various tests were made to

verify the design principles. The design of the barrel TRT module was completed and construction of the

device is well underway. Techniques were developed for manufacturing the carbon fibre support and forming

the radiator sheets. Tests are ongoing to determine the physical properties of the construction materials and

their resistance to the high radiation levels expected at the LHC. In view of the mass production of these

detectors, assembly and test methods are also being developed. Aspects of the overall co-ordination and

assembly were also considered: cabling, cooling systems, module insertion, etc.


CMS Central Tracker: In the Technical Proposal the silicon microstrip and MSGC barrel detectors were

supported on a common structure; these two devices are now physically separated. Both structures were

studied. In the silicon microstrip detector, the detecting elements are supported by a lightweight cooling tube.

Prototypes of this tube were made. The barrel MSGC design also evolved and tests and calculations of this

new design were performed. Studies of the cooling technique are well advanced. A robot for inserting the

detecting elements into the support structure was tested. The tracker alignment system using CCD cameras

that observe point light sources is under study. The group also participated in the design of the overall support

structure and in various aspects of the integration (cabling, cooling, etc.).

High-pressure hydrogen targets: Several targets for both PS195 and PS197 were made. New fabrication

methods developed in the group resulted in more reliable targets.

CHORUS and emulsions: The emulsion pouring and development facilities were maintained by the group.

This year there was a great deal of activity in this field.

Wire stretching facility: Wire chamber production continued to be an important part of the group’s

activities. Novel, lightweight, straw chambers that can be more easily assembled were developed and are at

present being tested.

Scintillator Section: The section manufactured and repaired scintillation devices for CERN user groups.

Thin Films and Glass Section: Glass blowing, glass and ceramic machining, and the production of thin

film deposits were carried out in this section. The production of caesium iodide solid photo-cathodes for the

development of large size RICH detectors (RD26), and finding means of producing metalized coatings for

MSGC plates (RD28) continued to be major activities, as did the high reflection coating of PbWO, for the

CMS EM calorimeter.

In an attempt to understand the effect of environmental factors, vibrations in the LEP experiments were

investigated and this work is being used to predict the behaviour of the precise trackers for the LHC. The

effects of humidity on carbon fibre composites are also being studied.

Technical Assistance Group 2 (TA2)

In 1995 the PPE-TA2 Group provided technical support for several experiments.

As in the past, one of the main activities concerned the operation and upgrading of the DELPHI Barrel

RICH Detector. During the whole 1995 LEP run, all the subsystems under the responsibility of the group ran

smoothly and contributed to the successful data taking of the collaboration. The new cold separator, designed

and constructed in the group in 1994 to increase the reliability of the gas radiator circuit, was installed during

the 1994-95 LEP shutdown, and operated successfully till the end of the run. |

The OMEGA spectrometer operated very successfully in 1995: WA 102 was installed during the 1994-95

shutdown and took the expected proton data before the short August shutdown, when it was removed and

replaced by the WA 97 set-up, which worked smoothly till the end of the 1995 run, taking both proton and Pb

ions data.


CMS support concerned two activities, both related to the ECAL project: TA2 designed an improved

version of the Barrel Pre-Shower Counter and started an R&D activity on temperature control and monitoring

for the PbWO, cerystals. Test apparatus was designed, built, and operated in order to study the response of the

crystals to temperature variations, to select and compare various temperature sensors and read-out methods,

and to design and compare different cooling systems. One’ of these set-ups was also used to check the

performance of the reflective coating deposited on the crystals by TAl colleagues. In parallel, on an

unforeseen request from CMS, a novel cooling system was designed, built, tested, and installed in record time,

and operated very successfully in the different ECAL prototypes installed at the test beams.

For ALICE, in view of the Technical Proposal, the group actively participated in the general layout of the

experimental set-up, in the design of the TPC and the HMPID, and in the integration of the various detectors;

the proposals were approved by the collaboration and introduced in the Technical Proposal.

A very efficient gas distribution for the NOMAD Pre-Shower Counter was designed and successfully

tested on a prototype. It will be constructed and installed in collaboration with the Lausanne I.P.N. during the

1995-96 shutdown.

For many years, TA2 has provided components for wire chamber wiring to different experiments and

groups; in 1995 this effort continued, satisfying many requests from the different laboratories of our

community.

GDD/Pad Detector Section

The section pursued three activities:

NA44: the Threshold Imaging Cherenkov detector (TIC), built by the section in 1994, was equipped with

two large caesium iodide photocathodes (PC) of size 25 x 80 cm? in order to replace the TMAE vapour (the

existing photo converting element). These two PCs, tested at the PS/T11 beam, showed a satisfactory quantum

efficiency. The use of thin caesium iodide films allowed the photo conversion gap to be reduced to a minimum

thickness, making the detector less sensitive to the high level of ionizing background found during lead beam

operation. The TIC was successfully operated at lead beam rate up to a few 10° per spill. For the first time,

particle identification was achieved in an experiment using a caesium iodide-based photo detector.

The tracking pad and strip chambers, as well as the TIC, were all equipped with new front-end and read-

out electronics based on GASSIPLEX chips and C-RAMS VME modules. The pad chamber was included in

the 1st-level trigger by implementing a fast anode read-out.

RD-26: the section was involved in the production of four new large caesium iodide photocathodes. They

were evaluated at the PS/T11 test beam using a fast RICH detector, and their quantum efficiency was found to

be satisfactory. For more information see the RD-26 section.

ALICE: the section participated in the elaboration and design of the High Momentum PID system

(HMPID), where a caesium iodide fast RICH was retained as the base line choice for a 12 m? detector

coverage.


Optical Fibres Group (OF)

The group continued, within the framework of the RD7 Collaboration and the LAA project, to investigate

and improve the properties of scintillating fibres for particle tracking, and to develop a new optoelectronic

read-out to demonstrate the feasibility of such a detector in present and future high-energy physics

experiments.

During 1995, much of the work concentrated on the new optoelectronic read-out, called the ISPA-tube,

which is now operative and completely characterized. The evacuated tube contains a photocathode facing a

silicon pixel chip (from the RD19 Collaboration). Photoelectrons, accelerated in an electrostatic potential, hit

the silicon pixels and generate enough electron-hole pairs to be detected. Apart from its performances in the

read-out of scintillating fibres for particle tracking (track centre-of-gravity precision: 15 um, track angular

resolution: 10 mrad), the ISPA-tube was used in position-sensitive photon counting experiments and its single-

photon detection capability was demonstrated. The tube also read out YAP-crystal arrays detecting low-energy

gamma rays. The intrinsic spatial resolution was 300 um and the efficiency of detection exceeded 70%.

Finally, low-energy beta rays were detected using scintillator sheets read out by an ISPA-tube. The achieved

spatial resolution was below 100 um, and the typical sensitivity to the beta energy was 0.5 photoelectron

per keV.

In parallel, the group was involved in new developments and applications of single- and multi-pixel hybrid

detectors.

In 1995 the group published two papers in international journals, two papers in conference proceedings,

and two CERN reports.


Electronics & Computing for Physics

Division

ECP Division

The Division provides front-end electronics, trigger, data-acquisition, online and offline support to the

LEP, PS, and SPS experiments and, since a couple of years, to the LHC test beams facilities. In parallel it is in

charge of physics-related electronics and computing activities for new experiments and R&D projects.

Baseline technical service and support is offered to the experimental groups.

In 1995, the Division was organized into two units, headed by deputy division leaders with executive

power: the Electronics Unit and the Computing Unit. During the year a restructuring aimed at optimizing the

resources of the division, taking into account the ongoing commitments and the new experiments’ requests,

was worked out. It will become effective in 1996.

The Division is traditionally host to the Secretariats of several committees: the SPS and LEAR

Experiments Committee (SPSLC), the LEP Experiments Committee (LEPC), the LHC Experiments

Committee (LHCC), and the Research Board (RB).

Electronics Unit

In 1995, the Electronics Unit contained seven groups distributed over three major activities:

microelectronics design, system design, and support. One group is fully dedicated to microelectronics. The

three other design groups develop and support electronics systems for a number of CERN experiments and

detectors. Each group can handle designs in the fields of front-ends, triggers, DAQ and controls. The three

support groups provide assistance with the experimental areas, control and safety electronics systems,

electronics pool equipment, instrumentation, quality assurance, and product engineering.

Microelectronics Research and Development Group (MIC)

The main effort has once again been on R&D in semiconductor detectors, custom integrated circuits, and

systems for the LHC experiments through contributions to RD2, RD8, RD9, RD12, RD19, RD23, RD29,

RD31, and RD36. The projects RD2 and RD36 were completed and their results have been integrated into the

ATLAS Silicon Central Tracker (SCT) and the CMS Preshower detectors, respectively. Developments

continued for the fixed-target experiments WA97 and NA48. The Group continued to foster collaboration and

growth of microelectronics expertise in the HEP community by hosting visitors and students, and by

organizing the Microelectronics User Group (MUG) meetings.

Electronics & Computing for Physics Division

„SU "olabor: |

“ ec jointly with

orgtion,

The GASSIPLEX chip for analog readout of gaseous detectors was ported to the 0.7 jım CMOS process of

Mietec. The HADES experiment at GSI, Darmstadt took delivery of 300 GASSIPLEX chips. A new integrated

front-end (DIGIPLEX) is under development in collaboration with IMEC (B) for the RICH chamber of

ALICE. DIGIPLEX enhances the GASSIPLEX architecture with digital signal processing functions (ADC,

pedestal subtraction, and zero-suppression).

A prototype 32-channel, sub-nanosecond Time to Digital Converter (TDC) chip suitable for muon detector

electronics in ATLAS and CMS was produced in the 0.7 um CMOS technology from ES2 (F). A low-volume

production run is under way in order to allow better characterization. Using this chip CAEN (T) developed a

64-channel VME board for applications in experiments. Good progress was made in developing a high-

resolution TDC (- 50 ps) prototype for ALICE.

After prototyping of the critical subcircuits, a prototype of the complete receiver chip (TTCrx) for the

clock and trigger distribution system of the LHC experiments was fabricated by the 0.7 um CMOS process of

ES2. In collaboration with RD23, a proposal for the embedded clock and trigger distribution and slow control

system of the CMS inner tracker is being developed.

The special purpose Trigger and Zero Suppression ASIC for the Data Concentrator of the NA48

experiment has been fabricated and is currently under test in a reduced version of the final readout card. A

memory controller ASIC for the readout has also been designed and tested successfully.

In preparation for the environment at the LHC, radiation damage effects in semiconductor detectors and

electronics have continued to be studied. The RD9 demonstrator programme for radiation-hard electronics

implemented in the HSOT3-HD 1.2 um SOI-CMOS process from Thomson TCS (F) produced a new low-

power, 11-bit, 20 MHz ADC. Measurements of the prototype agree with the SPICE sımulation and are close to

a previously developed radiation-soft version. This technology has also been used to demonstrate an integrated

front-end consisting of a large dynamic range amplifier and an analog memory suitable for the CMS

preshower detector.

In collaboration with RD29 and ATLAS, 32-channel demonstrators of ‘analog’ and ‘binary’ integrated

front-ends for the SCT tracker were developed in the radiation-hard DMILL process (CEA-LETD. A new

DMILL BiCMOS amplifier with a bipolar input was designed and tested in collaboration with the Institute of

Physics of Cracow. After 20 Mrad of gamma irradiation the parallel noise increased by less than 20%, and

total noise was measured as 1400 e” r.m.s. for an input capacitance of 20 pF and a pulse peaking time of 26 ns.

In addition, the study of the radiation hardness of advanced submicron and deep submicron CMOS processes

was started in collaboration with Mietec (B), SGS Thomson (I), IBM and CNET (F). First results indicate that

some advanced submicron CMOS processes may exhibit an unexpectedly high tolerance to radiation.

The damage induced in silicon detectors by pions, the main source of secondary particles for the LHC

trackers, was investigated and found to be similar within 20% to the damage induced by protons and neutrons.

A systematic study of proton irradiation of silicon detectors made from crystals with a large range of

resistivity (1.5-80 kQ cm) showed a linear dependence of the conduction-type inversion point with fluence.

The undesirable long-term reverse annealing effect is essentially independent of the resistivity. There is some

evidence that this effect could depend on the nature and the concentration of the impurities in the initial

crystal. Consequently, an R&D Collaboration has been initiated with institutes from ATLAS and CMS to

further investigate this point.


The Group continued to contribute to RD31 by demonstrating event building at frequencies up to 40 kHz

in a small system based on an ATM switch from Alcatel Bell Telephone (B), plus VME to ATM adapters and

traffic generators developed within the project.

Electronics Design Group (EDO)

The Electronic Design Group ‘O’ was created in November 1994 as a result of the merger of the former

EDA and EDE Groups. One of the main goals of this merger was to strengthen the contribution of the division

to the design and manufacture of the NA48 liquid krypton (LKr) calorimeter electronics. Since October 1995,

the Group has full responsibility for this electronics and major progress was made over the past twelve

months. This was achieved without impinging on the other major commitments of the Group, namely: RD24,

CPLEAR and DELPHI operations, together with a few activities around ALEPH, NA47, RD20, and ALICE.

The Group should be in a position to focus on ALICE and LHC-B as from the middle of 1996.

The main achievements of the Front-end sections of the Group were:

For NA48, the prototype of the Calorimeter Pipeline Digitizer (CPD) was tested in the second half of the

year following the successful delivery of two ASICs, a shaper in an AMS (A) BiCMOS process and a gate

array. A tender was placed for the manufacture of the 250 modules and the order to RDT (DK) was approved

by the Finance Committee in September. The final design for production at RDT is being prepared in the light

of the improvements identified during the test of the prototype. The Data Concentrator (DC) level-2 trigger

system associated with the CPD was specified in the spring and designed in collaboration with the

MICroelectronics Group of ECP. The system is installed in two crates and comprises 32 DC Processors

(DCPs), and 1 DC Controller (DCC). A ‘single-channel’ version of the DCP has recently been manufactured.

It is being tested. The DCC prototype has also been built and it is 70% tested. This trigger system involves a

gate array from Motorola and a Multi Chip Module which was subcontracted to IBM Vimercate (I). Prototypes

will be delivered two months after CERN approval of the ‘single channel’. Point-to-point Fibre Optical Links

(FOLs) connect the 250 CPDs to the 32 DCPs, which, in turn, send validated data to the Data Merger of the

experiment. Several FOL interfaces have been designed, all with the same link protocol.

In addition, the 15 Look-Up Table modules for the LKr first-level trigger system were produced, tested,

and delivered to the experiment.

The Front-end sections of the Group also supervised the design of ancillary FASTBUS modules (clock

fan-outs and opto-coupled interfaces).

For DELPHI, manufacture by CAEN of 32 fully tested New Pandora units which will be installed during

the 1995/96 winter shutdown.

For ALEPH, production of 12 New Analog Fanout units and one Digital Fanout unit for the readout control

of the microvertex detector, tested and delivered to the experiment. They are installed and working.

The 1995 design activities of ECP-EDO-DQ Data Acquisition section were centred around the PCI, SCI,

VME and FASTBUS bus standards for DAQ. The task is to prepare scalable DAQ systems components for

LHC and to design modules for immediate use in the NA48 experiment. Information bulletins are available on

the Web under http://sunshine.cern.ch:8080/.


The crate interconnect is based on a bridge between the PCI bus on VME modules, allowing VME to be

interconnected via a 200 Mbyte/s SCI ringlet cable. The bridge was implemented as a mezzanine card

according to the new IEEE 1386 mezzanine standard (PMC) and constitutes the first PMC designed at CERN.

It involved VHDL synthesis of PCI slave/master functions into very high density ORCA FPFAs. A specific

VHDL function is the chain-DMA engine for very high speed autoscan of random data. The PMCs were tested

on commercial PowerPC modules under the real-time Lynx-OS system. This required initialization and test

utilities to be written in the C language.

The computer interconnect is a similar bridge, in the form of a standard PCI plug-in card for commercial

computers. The bridge was tested on an Intel Pentium system running Windows 95 and Linux. Both the crate

and the computer interconnect are working within a four-node ringlet test, ready for laboratory benchmarking

and further connection to commercial SCI bridges like for Sun Sparcstations.

The section is collaborating with Digital on the connection of an NT-based Alpha workstation via the PCI-

SCI bridge.

The DSP-based bridge design of RD24 for SCI was completed and delivered to the ATLAS Collaboration.

Its architecture is being reviewed and planned to be re-used on a PCI card as plug-in data-buffer processor.

The VME-PCI bridge is an auxiliary design of a processorless VME mother card with two PMC mezzanine

slots. All functions of this bridge are based on a single VME-PCI bridge chip with DMA support. This bridge

is a low-cost alternative to processor-based bridges with the advantage of not involving any software for its

transfer functions. In addition, it can carry a second PCI mezzanine and therefore allows for architectural

extensions such as insertion of DSP coprocessors. Prototype production has been launched.

The design of NA48’s readout modules, after commissioning of the VFIFO, has continued and led to the

production of 32 RIO TIC/DAT general-purpose V/O signal interface cards for the RIO8260 VME readout

processors. The design of the NA48 optical drivers and receivers which receive the trigger time-stamp

information and convert them into data formats for the RIO processor was completed.

Electronics Design Group (EDI)

The EDI Group has kept its long-standing commitments to LEP and fixed-target neutrino experiments.

Maintenance and support were provided for the readout electronics of the ALEPH SıCal luminosity monitor

and of the TPC, including participation in the upgrade of the TPD module test bench system. In CHORUS, the

EDI Group has provided operational support, as in the previous year, for the intensified CCD cameras and HV/

gating systems developed for the readout of the scintillating fibre trackers. The pulsed light-emitting diodes

calibration system developed for the NOMAD electromagnetic calorimeter (Pb-glass blocks) has confirmed its

excellent long-term stability.

A major part of the Group activity has been dedicated to the participation in the projects RD16 (FERMI),

RD23 (fibre optic links), and the CMS (forward) preshower readout electronics.

In the FERMI project, second-generation prototypes of the different ASICs were developed in order to

adapt them to the requirements of the actual detectors as well as the Trigger and DAQ systems of the

experiments. In the analog chain an improved version of the 10-bit 70 MHz ADC was manufactured in the

AMS 0.8 um CMOS technology and a second version of the radiation-hard DMILL compressor, including

line driver, is under test.

The demonstrator version of the digital part, consisting of Channel ASIC, Filter ASIC and Service ASIC

was fully tested during 1995. Improved versions of these ASICs are currently being manufactured.


Readout modules were built using the demonstrator version of the ASICs and a dynamic range of more

than 15 bits with a resolution of 10 bits was achieved. Microsystem test substrates and test vehicles were

produced in order to assure full understanding of the technology.

Beam tests with different detector prototypes, both from ATLAS and CMS, were executed with up to

100 FERMI readout channels installed on the detectors. These tests show that the performance of FERMI

fulfils the detector requirements. |

A new microsystem, aimed at the CMS implementation, is under study. A MCM test engine was produced

in order to evaluate different assembly techniques, like solderless flip-chip bonding as well as to address

questions of overall reliability, thermal properties, packaging, etc.

In RD23, further progress was made in the development of point-to-point fibre optic links for signal

transfer in the front-end electronics of LHC trackers. The baseline technology consists of passive transmitters

(semiconductor reflective electro-optic modulators) and hybrid transceivers. Extensive gamma-ray irradiation

measurements (up to 20 Mrad) with low and high dose rates were carried out on modulators and fibres. In the

analog mode, the long-term link stability was monitored over more than 3000 hours of continuous operation.

Digital mode performance was also assessed. A range of fast, very low-noise receiver amplifiers was

developed. Various active (laser) transmitters were also evaluated. The work is carried out in close contact with

the CMS and ATLAS Collaborations.

In continuation of the work started in the previous year, a substantial contribution was made to the

development of the controller, interface and dedicated test bench for the DYNLDR chip (developed in the MIC

Group) for the readout of the CMS ECAL preshower detector. A specific team has been set up in the Group for

this project.

Electronics Design Group (EDU)

The EDU Group designs and supports front-end, trigger, and readout electronics for experiments. It is also

developing expertise on high-speed data links for the future LHC experiments.

In 1995 two Omega experiments were supported (WA91, WA97).

In WA97, two major 1994 developments were successfully used: the readout electronics of the PAD

chambers (12 000 channels) and of the silicon pixel detectors (300 000 channels). The VLSI chip for the

readout of the new silicon pixel detector was developed and the test of the detector performed in view of the

installation of a new telescope in 1996.

The OPAL Central Trigger Logic was redesigned in order to include a new detector in 1996. Additional

boards were built and installed to allow the silicon tungsten forward calorimeter to run with the new bunch

structure.

A FASTBUS test board for the ALEPH TPC digitizer was produced.

The NOMAD trigger distribution board (Notrimo, VME standard) was produced and used during the 1995

data taking. Help for the repair of the chambers was provided.


In NA48, three HiPPI interfaces, built in collaboration with DEC, were successfully used in the September

run. A new joint project began with the aim of designing a HiPPI-PCI interface which will allow NA48 to

upgrade their workstations in 1997. As part of this project, commercial solutions are also being evaluated. The

four optical links built by the HSI project also worked without error during the run. Thirteen more optical links

will be installed in the next two years.

For LHC experiments and associated R&D, the Group has been involved in different domains:

Front-end components evaluation and implementation in a test beam was done for the CMS tracker.

Significant work was done for the ATLAS TRT test beam, where a prototype sector was successfully

tested with an LHC prototype electronics. In parallel, simulation work and system design for the final

readout were performed.

Studies of high-density connectors and thin cables for both high-voltage and signal distribution were

carried out in collaboration with external firms.

A Central Level-1 Trigger Processor (RD27 and ATLAS) demonstrator was designed and should be

completed and in use in 1996. |

The use of the RD12 Trigger, Timing and Control (TTC) system in ATLAS was studied. A test board

for the TTC receiver chip was made.

The support to the LAr calorimeter (former RD3), the Tile Hadronic calorimeter (former RD34), and

the muon chambers tests continued.

Support for both HiPPI and Fibre Channel was provided in the DRDC projects RD11, RD12, RD13.

Support was provided to CN Division for the installation of HiPPI in the computer centre. WWW pages

for High Speed Interconnects (http://www.cern.ch/HSY/Welcome.html) were created.

A specification for a simple optical link, the S-LINK, was drafted. The S-LINK specification was

presented to the LHC collaborations during a workshop devoted to high-speed links and was well

received. Work has begun, in collaboration with a team from Hungary, on implementations for use in

LHC experiments.

Electronics Support and Infrastructure Group (ESD)

The ESI Group is in charge of the neutrino beam for CHORUS and NOMAD and provides support in the

field of controls, safety systems, and operation to the four LEP experiments ALEPH, DELPHI, L3, OPAL and

to ISOLDE. The staff is detached in the case of ISOLDE.

New activities oriented towards LHC experiments started in 1995: support for construction of an X-ray

scanner for ATLAS muon chambers and definition of resources to take charge of the control systems for the

magnets of the LHC experiments.

The ESI Group includes four sections: Experimental Activities (EA), Safety and Operation (SO), Technical

Support (TS), and Controls (CL) who ensured the following objectives in 1995:


— Continuation of the operation and maintenance of the neutrino beam line for the production runs of the

CHORUS and NOMAD experiments. The beam line operated successfully from mid-April up to the

end of the 1995 physics run. The total time lost for hardware or software related problems along the

beam line was insignificant. The experiments benefited from an overall exceptional SPS efficiency

during the year.

— Permanent 24-hour operation of the safety systems of the LEP experiments and related zones (GSS—

General Safety System, SDN—Systemes de Detection et de Neutralisation de fuites de gaz, ALEPH

Barrack Safety system); all Equipment Control Assemblies (ECAs) of the four LEP experiments were

upgraded to the VME standard and the four GSS centrals were equipped with the new simplified

version called ‘GSS-Light’, thus ending all re-engineering work foreseen in all experiment sites. (Each

GSS central treats the information received from the ECAs, makes diagnoses and acts in consequence.)

-— Organization of LEP support meetings and responsibility for the territorial safety of the LEP

experiments.

— Provision of controls and exploitation support for the ALEPH and DELPHI superconducting magnets

and counting rooms safety systems.

— Continuation of the general G64 and electronics support for DELPHI, ALEPH, LEAR, and WANF

slow controls with progressive extension to CMS.

— Assurance as in past years of direct technical support by detachment to:

ISOLDE (development of beam instrumentation; specification, ordering, and installation of the new

radioactive target manipulator robot delivered as a turn-key system from industry; maintenance of

H.T. power supplies).

L3 (maintenance of the safety stations based on the BBL3 system).

— Collaboration on the ATLAS-MDT muon chamber X-ray project for the construction of a prototype

scanner. One small prototype chamber was measured with one single X-ray source at the end of 1995.

— Preparation of the Group structure for future control activities on the superconducting magnets of the

LHC experiments.

Electronics System Support Group (ESS)

The ESS Group provides support, mainly within the Research Sector, for modular electronics systems

(VMEbus, CAMAC, NIM, etc.), for crates and power supplies, for high-voltage systems, and for laboratory

instruments.

During 1995 more than 25 new types of equipment were evaluated and tested on request by various

experiments. Several new types of front-end modules, ADCs, TDCs, counters, etc., were evaluated and

successful candidates added to the Electronics Pool. New types of high-voltage modules and some laboratory

instruments were also evaluated and added to the Electronics Pool.

The Group developed and assembled a number of OSCAR turn-key data acquisition systems based on the

CASCADE data acquisition software package provided by the ECP/DS software team. Several experiments


and test beams such as NOMAD, NA44, Energy Amplifier, etc., have made use of such systems and the Group

provided the necessary installation and first-line support. In addition, the Group evaluated and integrated new

VMEbus-based devices such as FDL and DLT in view of extending the use of CASCADE.

New processor modules based on the PowerPC processor family were evaluated in order to find successors

to the FIC 8234 processor module which is widely used at CERN today. Extended benchmark and

comparative tests were made.

The Group provides a quality control service to users and in 1995 more than 3000 units of various types

were verified and more than 700 units were repaired. Most repairs are subcontracted outside CERN.

The Group is responsible for the VMEbus support at CERN and as such the Group drives and co-ordinates

the standardization activities. Two workshops were organized in 1995 to discuss VMEbus extensions for

Physics and a ‘Recommended Practices document’ has been established. In collaboration with other HEP

laboratories in Europe, the USA, and Japan, proposals for extensions to the VMEbus standard have been

worked out and addressed to the VITA standards organization.

The Group also provides an Electronics Pool facility which contains about 40 000 items of 2000 different

types. There are about 300 clients, mainly in the Research Sector, who rent equipment more or less

permanently to a value of 40 MCHE. In addition about 3500 units to a value of 10 MCHF are rented each year

and a similar number are returned to the Pool.

In 1995 the Pool purchased a range of new equipment to a value of 2.7 MCHEF. All equipment was tested,

accepted, and delivered to the clients. The main clients in 1995 were NA48, NA49, NOMAD, CHORUS, and

NASO.

The repair of Pool items is largely subcontracted outside CERN and in 1995 this amounted to 0.3 MCHF.

The rental fee paid by the Pool clients in 1995 amounted to 2.5 MCHF which was used to finance the

purchase of new equipment and the subcontracted repairs.

A number of improvements were made in the administration and handling of the Pool. A new rental

scheme was implemented in September. The introduction of bar-codes for the Pool items has started and a

general review and classification of all Pool items is under way.

Product Engineering and Support Group (PES)

The three sections in the PES Group assisted the electronics designers in other groups with their different

design activities. Work was carried out for experiments at the PS, SPS, and LEP accelerators and the LHC test

beams for design activities in accelerator divisions, and for specific R&D projects.

The Design Support (DS) section is responsible for the installation and maintenance of software which is

used by the electronics engineers in the ECP division and other divisions. About 200 home directories of PC

users were installed on a new server.

Programming help for PC and Macintosh users is an important part of the Group activities. As an example,

the test system for the ALEPH TPC electronics is now operational. It uses the visual programming language

LabView and a new interface from industry.

A generic Central Trigger Processor for RD27 has been designed and new FPGA components have been

evaluated using VHDL and synthesis tools.


In the framework of RD3, and nowadays of the ATLAS experiment, the design of the electrodes of the

barrel calorimeter continued. From a market survey the production of some 20 full-size electrodes was given

to industry. The design of the electrodes for the end-caps has started.

The Layout (LT) section continued its support for designers by making layouts for printed circuit boards

and hybrids. While PCAD continued to be heavily used as a CAD system for relatively simple designs, more

complex printed circuit boards were prepared using Concept and Allegro. Most prominent examples are for

the NA48 experiment and for R&D projects. A multi-chip module was laid out and is near to completion.

Ceramic circuits were developed and are now in production.

The process of creation of components for the libraries was partially reorganized. There is now one set of

libraries, which can be used by everybody at CERN.

The Workshop (WS) section is responsible for the cabling and repair of prototypes and small series. The

section again served clients from many experiments, like CHORUS, DELPHI, L3, NA47, NA48, NOMAD,

WAS0, and ISOLDE. The new workshop for SMD components was installed. A new unsoldering-resoldering

system for high density components has been purchased and is currently being installed.

Two examples to illustrate the kind of work executed:

A series of boards with 21 layers and a thick ground layer had to be soldered manually under the

microscope. Its thermal mass was too high for standard infrared reflow soldering.

For conventional cabling a stand-alone test system was designed with the engineer from the experiment

concerned. It will be shipped to industry to be used for the testing of some thousand daughter boards.

Computing Unit

In 1995, the Computing Unit contained five groups, organized according to related activities. These

include development and support of readout architecture, trigger, data acquisition and test systems, data

processing systems, software technologies and controls. Group members are either directly attached to

experiments or work on projects, mainly in collaboration with other groups, divisions, or outside users.

Readout Architecture Group (RA)

The main activity of the RA Group is the research and development of advanced new trigger, control,

readout, and data-handling system architectures for LHC experiments. During 1995 a large part of the R&D

work was completed or continued within ATLAS and CMS special projects.

RD11 - Embedded Architectures for Second-Level Triggering in LHC Experiments: EAST

Collaboration

EAST terminated its activities as a separate R&D project at the end of 1995. The problem decomposition

into:

— front-end buffering and collection of raw data for regions of interest (Rol)


feature extraction: local processing of data in a Rol of a subdetector

global decision: Rol and event processing

was taken over by ATLAS, and the implementation options (farm-based and data-driven, respectively) are still

being explored.

The activities of EAST in 1995 were the following:

Pipelined data-driven systems were exhaustively demonstrated: a TRT Router, the Enable processor

and DecPerle performed in beam and laboratory tests, a generalization of these designs will be tested

in 1996 as part of the ATLAS programme. These FPGA-based devices have been shown to keep up

with the 100 KHz input rate, for all algorithm parts, and could thus implement a full level-2 trigger.

Components of a farm-based solution, based on DSPs (C40 from Texas Instruments) and DS links with

a C104 switch (C104, from Inmos), were brought to CERN for testing in the laboratory and in the

ATLAS test beam; these tests will be continued with more complete equipment in 1996. SCI interfaces

and a computer farm based on Alpha processors will also be tested.

A model written in the simulation language Modsim II, and describing farm-based solutions, and in

particular the C40/C104-based version, was developed, and will next be tuned in detail so that

extrapolation to a full system becomes possible.

The participation in the Esprit project AFRODITE was continued, and allowed a detailed assessment of

a formal object-oriented language (VDM++) for the applications of hardware and software

specification of the level-2 trigger. AFRODITE terminated its developments successfully at the end

of 1995.

An improved version of the SLATE emulator was designed and built; all existing SLATEs are now

being upgraded to satisfy the improved specifications, and will be available for future testing.

A benchmark suite for measuring combined communication/computing performance of parallel

systems was developed, and is now being used to evaluate candidates for computer farms, in particular

large commercial parallel systems (HPCN systems).

RD12 - Readout System Test Benches

The project has been concentrated in two activities:

the Timing, Triggei and Control (TTC) systems for LHC Detectors;

the Dual Port Memory (DPM) structures in CMS data acquisition.

The RD12 Collaboration has been restructured to concentrate on timing, trigger and control system

development and now includes representatives from ALICE, ATLAS, CMS, and LHC-B as well as industrial

partners.

The DPM developments have been included in the CMS prototyping programme.


Timing, Trigger and Control (TTC) Systems for LHC Detectors

The TTC project is developing a multi-function optoelectronic distribution system which can meet the

TTC requirements of the different subdetectors of the LHC experiments. The system distributes the LHC

bunch-crossing clock, level-1 trigger decisions and bunch and event numbers, as well as test signals and

broadcast commands. It incorporates programmable coarse and fine deskew facilities to compensate for

different particle flight times and detector, electronics, propagation and test generator delays. It can also

transmit asynchronous slow controls and data such as individually-addressed channel enables and calibration

parameters to several thousand destinations.

During 1995 several TTC laser transmitter crates were produced, a preliminary version of the VMEbus

interface (TTCvi) was developed by ECP-EDU and the timing receiver ASIC (TTCrx) was designed by ECP-

MIC and submitted for fabrication. Prototype versions of the subminiature *RD12’ optical connector and

active device mount were manufactured by our industrial partners and irradiation tests of the photodetector/

preamplifier were commenced with satisfactory results.

CMS Data Acquisition Dual Port Memories

The central part of the CMS data acquisition is made up of an event building designed around a

telecommunication cross-bar switch controlled by input and output buffers.

At the beginning of 1995 a description of most of the functions required in the input (RDPM) and output

(SFT) buffers was written in a report CMS-TN 954.

A workshop on DPM was organized in March to give the opportunity to share information with other

experiments.

The design and construction of the first prototype RDPM-P1 was carried out in the first half of the year. It

is a VME module containing 2 Mbytes of buffer memory with dual-port capability and an aggregate

bandwidth of 200 Mbytes. At the same time a test board (RENG) was constructed in order to test the memory

management functions of the RDPM-P1.

The second half of the year was dedicated to the test environment: the VME framework controlled by

LabView (under MacOs). On the VMEbus, high-speed data generators and receivers (FDPM) were used to test

the data paths while the RENG provides the test stimulus for the input and output activity.

In the second half of 1995 a definition of a second prototype was also frozen. It will contain four major

blocks: a memory management unit, amemory block, an input from VME64, and an output to the PCI. The

four blocks led to four minor projects. The assembly of these RDPM-P2 components is expected by the end

of 1996.

In the course of the year a new software tool was acquired (VisualHDL) to enable the sharing of hardware

descriptions within the collaboration. The Cadence Allegro system was used for the DPM-P1 design. Some

follow-up on ALTERA new technology was also made.


RD13 - A Scalable Data-Taking System at a Test Beam for LHC

A test beam readout facility was installed for the simultaneous test of LHC detectors, trigger and readout

electronics, together with the development of the supporting architecture in a multiprocessor environment. The

aim of the project is to build a system which incorporates all the functionality of a complete readout chain.

Emphasis is put on a highly modular design, such that new hardware and software developments can be

conveniently introduced. Exploiting this modularity, the set-up will evolve driven by progress in technologies

and new software developments.

The RD13 DAQ system has evolved to cope with the demanding requirements of a configurable multi-

detector set-up. The latest version of the RD13 DAQ system was used in the H8 test beam area by ATLAS sub-

detectors during 1995. Since June 1994, a number of functions have been completed and new features have

been added, including:

— The support for scaling in the number of detectors (data sources) was completed to include merging of

data coming from local detector acquisitions (event building), configuration description in terms of data

bases, support for the control of multiple acquisition systems by the run control module.

— The system is configurable via databases and supports stand-alone (one detector only taking data

without a data merging stage) and multi-detector set-ups. New databases to manage status and error

messages and to maintain run bookkeeping information have been developed based on object-oriented

software technology and tools.

— The Fast Data Link (FDL) hardware system from the CES company was integrated, as an optional

alternative to the VIC8251-based data merging.

— The recording subsystem was enhanced by support for labelled tapes (when recording data locally in

the test beam area), and integration of the central data recording system (recording events directly to

the CERN computer centre) developed by the CN Division.

GP-MIMD - General-Purpose Multiple-Instruction, Multiple-Data Machine

The GP-MIMD project to construct a 64-node T9000 Transputer computer was completed in the spring

with a successful demonstration in the CPLEAR experiment. The machine has been used to run extensive tests

to measure the performance of the machine’s interconnection network showing its potential for application ın

LHC experiments.

The EU-funded Harmony project is a collaboration with INMOS, Parsys, and CHORUS Systems of France

to develop the CHORUS operating system on the Transputer. This operating system has been used to

reconstruct brain images at the Höpital Cantonal de Gen&ve in collaboration with the University of Lausanne.

The speed at which these images are processed has been increased, using both the T9000 Transputer and DEC

Alpha processors. The project was completed in autumn.

The Macrame project, also funded by the EU, is a continuation of much of the work begun in GP-MIMD.

It aims to further develop and test the technology of high-performance switches and interconnects. The test

bench being constructed will be used as part of the ATLAS second-level trigger studies. The Arches EU

project began in December and will extend the work begun in Macrame to the study of high-speed, 1 Gbits/s

links developed by Bull.


Data-Acquisition Systems Group (DS)

During 1995, the ECP Data-Acquisition Systems Group (ECP-DS) provided support for the baseline

activity and continued its development programme.

DS ensured support and maintenance for the Group-provided software such as the MODEL packages, the

CASCADE data-acquisition system, and the packages for accessing VME, CAMAC, and FASTBUS.

The new VME-based CAMAC-Ethernet interface was commissioned and then used at L3; it allowed L3 to

get rid of the old Qbus-based interface which no longer matched their requirements.

The CASCADE data-acquisition system, used by NOMAD, performed very well. The NA44 experiment

has adopted it and used it successfully for its data acquisition in November.

Several enhancements were made to CASCADE:

— Anew run control based on the one developed for the OPAL experiment was introduced.

— New hardware platforms, such as the Scalable Coherent Interface (SCI) and the CES Fast Data Link

(FDL), were evaluated in the context of inter-stage links.

— Data recording on the Digital Linear Tape (DLT) was implemented in addition to the data storage

options already proposed.

CASCADE was also ported to the LynxÖOS operating system. A consolidation and optimization

programme, carried out throughout the year, resulted in a number of significant improvements in both

efficiency and reliability.

Members of the DS Group participated in experiments such as ALEPH, CHORUS, DELPHI, OPAL, the

Omega spectrometer and NA48; they actively contributed to the specific plans and activities of these

experiments. Other members of the Group were involved in R&D projects for future data-acquisition systems,

namely in RD13 (Scalable Data-Taking System), RD24 (Application of SCI to DAQ), and RD31 (Event

Building Based on ATM), and in the proposed LHC experiments ALICE and ATLAS.

Simulation, Reconstruction and Analysis Group (SA)

In 1995 the Group supported various offline activities of ongoing experiments while playing an active role

in the preparation of the Computing Technical Proposal of the CMS experiment and the evaluation of new

software methodologies.

The main responsibilities in DELPHI consisted in the running of the Computer Farm, DELFARM, the

running of the production, the DST analysis, and the support to detectors. The production Farm, DELFARM,

based on Alpha workstations running the DECUNIX system, performed the reconstruction of the real data

taken in 1995, several reprocessings of earlier data and various extracts of DSTs for physics analysis. An

innovation was the fact that computers from the Farm can now also be used as part of the CPU on SHIFT for

physics analysis. This was of great help during the busy periods before conferences. Another activity was a

major enhancement of the existing DELPHI graphics program in view of the interactive analysis of LEP 1.5

and LEP2 events. Detector support concerned mostly the alignment of the Microvertex detector and the


alignment and identification using the RICH. The responsibility for the management of the VAX cluster of

about 80 workstations running VMS is also with the Group.

During the 1995 running period the NOMAD (WA96) experiment took a large quantity of neutrino events

and muon calibration data, about 30 million triggers spread over 3000 cassettes. The members of the SA

Group working with NOMAD are strongly involved in writing the reconstruction package and in the

processing of the neutrino event data. A complete data production system for event processing on SHIFT, and

automatic computerized bookkeeping based on the HEPDB database have been created, together with an

interactive user interface based on WWW. During the year most of the event data was processed at least once.

The full NA44 software (reconstruction, analysis) was implemented on CERNSP and HPPLUS. The

interface to the new DAQ based on CASCADE was developed and commissioned.

In 1995, the CMS Technical Proposal was defended successfully, leading first to the LHCC and Research

Board recommendations for approval in 1995, and to the final approval of the project by the Director-General

on 31 January 1996.

A considerable amount of work on software was done to achieve full satisfaction of the bodies concerned

during the approval process. For example, the simulation program was developed further, so that detector

performance could be demonstrated also in different descoping and staging scenarios.

Discussions about the CMS Computing Model started, and a working group was formed. The first iteration

of the model will be described in the Computing Technical Proposal, due in December 1996.

A prototype demonstrating the usefulness of the new object-oriented (OO) programming technology was

created and successfully tested in the framework of the RD41 (Moose) project. However, much more work is

needed. CMS will also continue the close collaboration with the RD44 (GEANTA4) and RD45 (persistent

objects) projects.

In NA48, the Group participated in the running in the K12 kaon beams, with most of the charged

spectrometer installed. Central data recording, developed in collaboration with CN Division, was very

successfully introduced and used throughout, collecting 0.7 Tbyte of physics data on the Meiko-CS2. First

tests were made of parallel real-time event reconstruction. Data were taken and analysed from the LKr

calorimeter prototype in the H4 beam to evaluate the prototype CPD readout module. A clear framework has

been established for reconstruction of 1995 data and evolution towards the 1996 tests of a more complete

detector, including the LKr calorimeter. Design work has started on a data management system for full

production in 1997.

Programming Techniques Group (PT)

The Programming Techniques Group provides information, software tools, and consultancy to software

developers in the experimental teams, in order to help them produce better software. Having partnered the

original development of the WWW technology, it assists experiments in setting up information and

documentation systems.

The Software Technology Interest Group (STING) distributed about 100 news items and documents, and

maintained a regularly updated WWW service, averaging 4000 accesses per week and functioning as a

software engineering information guide.


The Software Development Tools Service (SDTS) grew to 20 tools, with eight added in 1995. One

hundred and thirty-seven active customers generated about 2000 accesses per week to the 400 Web pages

providing information on about 330 products. The SDTS also organized eight technical presentations,

including the MBONE transmitted computer seminar by James Rumbaugh on the Unified Method for OO

design.

ADAMO development and support led to considerable improvement in the performance of the indexing

functions, and a prototype of a generic WWW interface to ADAMO data files. DALI, the ALEPH event

display program, was further developed resulting in new presentation techniques from the study of

physiological aspects of the use of colour and of visualization of complex events in 3D. The DALI approach to

event display was presented extensively at the HEPVIS95 Workshop held at Fermilab.

The new ALEPH Finite State Machine (FSM2) was designed and developed with the participation of the

ALEPH Online Group to meet the new requirements of the ALEPH DAQ system. The FSM2 is a complete

redesign of the original FSM, implemented in C++ using the OMT methodology. The FSM2 was presented at

CHEP’95 in Rio de Janeiro.

The ALEPH online cluster was modified to replace VAX machines with Alpha servers and Alpha

workstations. The average data-taking efficiency during 1995 was the highest so far, reaching 95% during the

high-energy period at the end of the year.

The LIGHT (Life cycle Global HyperText) system to ‘hyperize’ software documentation on the WWW

had its first major application with the reconstruction program of ALEPH, Julia. The public Juli/ LIGHT Web

contains - 15 000 HTML pages and - 500 000 hypertext links, linking source code and its documentation.

Juli/LIGHT was presented at CHEP’95. WebSolver, an essential but generic ingredient of LIGHT, was

developed using commercial C++ libraries and permits dynamic resolution of logical pointers for WWW

pages, according to Local Resource Names (LRNs) rather than URLs.

FrameMaker and WebMaker templates for the UR and SR documents of the ESA Software Engineering

Standards (PSS-05) were developed as stand-alone deliverables, but plugable into a LIGHT documentation

system. They are being used by projects such as GEANT4 and the ATLAS Detector Control System.

The popular WebMaker system was transferred to Harlequin Ltd. WebMaker is a configurable generator of

webs from FrameMaker documents, was designed and developed in the Group, and was previously licensed to

over 3000 users world-wide. WebMaker is now available for UNIX, Mac and PC platforms, with a free

CERN-wide licence.

The PT Group took part in the EDMS (Engineering Data Management System) Task Force for the LHC to

define the User Requirements and the preparation of the call for tender. The EDMS will manage, store, and

control all information relevant to the design, construction, and exploitation of the LHC accelerator and

experiments during their complete life cycle.

Members of the Group gave a number of courses in 1995: a five-day course on “WWW for Physics’ in

May at the University of Bologna; an entire track on the same topic, at CSC’95 in Arles; a one-day ‘Hands-on

WebMaker Course’ at CERN; a four-hour course on ‘Software Development: People, Process, Technology’

was given at ES2I in Marseille.


Controls Group (CO)

The CO Group had four main objectives, namely:

— carry outresearch and development activities in the domain of slow control for future applications;

provide slow control software for some fixed-target experiments and for L3;

ensure maintenance for the above and the General Safety System for all four LEP experiments;

study the slow control requirements for the LHC experiments.

CICERO (Control Information system Concept based on Encapsulated Real-time Objects): The RD38

project was approved in 1994 by the DRDC. The project was proposed by seven institutes and eight industrial

partners. After a positive review in April 1995 the project was extended for a further year. After some concerns

expressed by two LHC experiments, the LCRB and the LHCC concluded that an orderly wind down of the

project should be assured. This is being studied so as to preserve investments and knowledge acquired during

the development phase.

GSS (General Surveillance System): The users’ requirements of the re-engineering of the GSS supervisor

were written in 1994. Owing to lack of resources it was decided not to implement this re-engineering. The

present GSS system is now frozen, only minor modifications will be considered if they do not show any

potential problems, an upgrade for DELPHI is being implemented. During the whole year the system—in its

frozen state—gave satisfaction to the users.

WANF (West Area Neutrino Facility): The upgrading of the control system requested by the users is being

implemented. The three Lynx systems are operational, a second BCT was added, three new ionization

chambers were introduced for evaluation, and the timing panel was totally redesigned.

NA48 experiment: The hardware for the first phase was installed, the implementation will be based on

WANF technology including the FactoryLink supervisor, however CAMAC will be replaced by VME. The

software licences were acquired, the three VME-based front-end systems were installed with the help of the

PS Division, and the commercial Man-Machine Interface package was evaluated. The first tests were carried

out in summer. The users’ requirements for the second phase of the slow controls were written, review

meetings were organized, the implementation is under way.

The global hardware architecture for the cryogenics already defined was partially tested. The configuration

of the cryogenics control room was finally accepted. The hardware including the PLCs in the cryogenics

control room is about to be installed. Communication between the PLCs and the software architecture still

needs to be tested.

L3: The new controls for the gas system and for the racks were installed and they will be operational for

the 1996 start-up of the LEP machine. FactoryLink is used as supervisor and VME as front end. The re-

engineering of the muon control system is under way. The implementation is being done in close collaboration

with industry. A new industrial supervisor will be implemented. As resources are very limited, a rigorous work

schedule was developed and is being monitored on a monthly basis.


LHC: Liaisons with ALICE, ATLAS and CMS have been established to ensure communications between

the ECP/CO Group and the experiments. Technical discussions have started particularly with ATLAS and

CMS. Some users’ requirements have been written. A separate communication channel was established with

the working group on gas which will deal with the four LHC experiments, the users’ requirements will be the

first document to be provided by the gas experts with the help of ECP/CO. A working group on field buses is

also active to define acommon policy for both machines and experiments.

www

After successfully starting off the World-Wide Web on its global conquest, and following the approval of

the LHC project, CERN decided to hand the development of the WWW technology to leading institutes of

informatics.

The WebCore project was transferred early in the year to INRIA (the Institut National pour la Recherche

en Informatique et en Automatique) and MIT (Massachusetts Institute of Technology).

INRIA and MIT now jointly host the WWW Consortium (W3C), which CERN helped set up. The

Consortium groups well over a hundred global companies from the computing industry and also large users

such as tyre maker Michelin or Airbus Industrie.

During the transition period in 1995, CERN and in particular the ECP Division continued to house the Web

team and run the Web project servers to ensure a smooth take-over by the Consortium which now produces the

reference software. This year therefore saw the last official release of Web software coming from CERN,

though the CERN copyright will remain attached to its code.

CERN also continues to participate in the organization of the International WWW academic conference

series, which it started in Geneva. The fifth one in Paris is expecting 3000 participants. CERN was also

instrumental in starting the European Commission’s project “Web for Schools’ which aims at giving

150 secondary schools in the Union access to the Web.

CERN itself continues to be a large user with many WWW servers on site, the main entry path being

simply http://www.cern.ch/. Coordination is through the central WWW service and provides improved access

features.

Many prizes were received for the conception of WWW, the most important one being the Association for

Computing Machinery’s Software System Award, shared by Tim Berners-Lee and Robert Cailliau /ECP for

WWW, and Marc Andreessen and Eric Bina for the Mosaic browser.


Computing & Networks Division

Summary

The year was marked by more of the rapid changes in information technology that now have to be dealt

with routinely. A major move to central UNIX services, replacing the CERNVM mainframe system, was

undertaken, and more stress was given to PCs as useful scientific platforms.

In this context, the Division provides support for users of desktop systems based on PC/Novell (the NICE

service), on various UNIX platforms, and on OpenVMS. Much of the focus of the activities in 1995 was on

the UNIX side, deployment of two major public login UNIX services (PLUS), completion of the so-called

CUTE architecture for the UNIX user environment and the beginning of user education for these services. All

this was aimed at preparing for the closure of the CERNVM service in 1996 and the migration of its user base

to other platforms. A part of this was a major effort to inform users both inside and outside CERN of the NICE

and CUTE architectures adopted for PC and UNIX users, respectively, and to help them select and migrate to

their preferred platform.

The services for physics data processing are provided within an overall architecture called CORE which

defines an application environment including standard interfaces for access to disk and magnetic tape storage.

CORE also defines standard management interfaces which enable a range of services with very different

performance characteristics to be operated as a coherent unit. During 1995, a contract was agreed with an

external company to take over some of the management and operational tasks of the CORE services. It is

expected that this outsourcing activity will be expanded during the coming year.

A new planning process was implemented for the CORE services during 1995. This provides the

experiments with full transparency of the allocation of resources and their associated costs, and also allows the

COCOTIME computing resource allocation committee, chaired by the Director for Research, to control the

full range of physics data processing services within the budget constraints.

The Division continued in its role of providing CERN-wide support of software for engineering design and

embedded microprocessors. The analog CAE suite of tools now includes a complex package for handling

integrity problems of high-speed signals and the move of EUCLID from VAX/VMS to UNIX made

considerable progress. It is planned to terminate this migration in 1996. Beyond the normal support tasks,

information exchange remained a high priority, with regular meetings with users, organization of training in

close collaboration with the training services and informatics support for this service, attendance at many

conferences and external user group meetings, and with the revival of the Computing Support for Engineering

Newsletter (CSENL).


Two LCRB projects, RD44 for a Simulation toolkit, and RD45 for Object Persistency have been

coordinated by the Division and have both made significant advances this year. Both projects will have a major

impact on the LHC software environment. At the same time planning and investigations have started to

understand what will be the equivalent of the CERN program library in the LHC era.

1995 was another very busy year in computer networking, with the start of a major recabling project, and

substantial evolution of Internet connectivity.

Distributed Services

NICE

1995 was a year of consolidation of the NICE services. The Netware 4 infrastructure was completed

although conversion of users from older 3.11 servers will continue into 1996. Suitable infrastructures for

supporting Windows/NT were investigated in the light of the increasing pressure of Windows/NT at CERN.

Windows 95 was chosen as the natural successor to the Windows 3.1 desktop system supported by NICE, and

the preliminary NICE 95 environment was made available for technical evaluation. The NICE user community

continued to grow during 1995 with more than 1400 regular users and more than 1700 registered MS Mail

accounts.

CERNVM Migration

As part of the migration away from CERNVM, much effort was put into designing, in collaboration with

other laboratories, notably DESY, a UNIX environment which could be offered to CERNVM users moving to

UNIX and which could be implemented across a range of platforms. This was presented to various user

communities and their reactions fed back into the design which is referred to as CUTE and which is deployed

on WGS and PLUS nodes as well as on individual users’ workstations.

Along with deployment of CUTE on various services, there was a campaign of user training begun with a

weekly series of short seminars dedicated to specific topics and the issuing of a large quantity of CERN-

written documentation ranging from single-page reference cards to large User Guides.

Public Login UNIX Servers

The formal introduction of the CERNSP Public Login Service in March has brought even more users to the

CUTE model for UNIX-based Interactive Computing. At the end of the year some 2200 users were registered

with about 850 different users active each week. This service runs on 16 nodes of CERN’s IBM SP2 system

and the interactive service is closely integrated with the SP2 batch service which uses IBM’s LoadLeveler

scheduler. The CERNSP service is seen as the general-purpose UNIX-based interactive service and by the end

of the year it was hosting an increasing number of services previously run on CERNVM. Doubtless many

more will migrate over the next few months.


A complementary HP-UX service, HPPLUS, was introduced in the middle of the year, aimed primarily at

the LEP experiments. Some 1100 accounts were registered on the service of which almost 300 are used in a

week. An initial testing period by DELPHI during the summer was followed by a period of close collaboration

with OPAL and the formal introduction of the service in November. Amongst other things, collaboration with

OPAL led to a customized version of the fvwm window manager which has been adopted as the default for all

WGS and PLUS clusters—the CERNSP interface changing in early December. Adopting such standard

interfaces on all platforms is seen as being of significant benefit to the increasing number of users who need

access to more than one platform.

The performance monitoring tools introduced at the end of 1994 have shown their worth and we are now

able to track usage and performance for the different clusters over time. There were many accounts duplicated

across the different CUTE services and a significant number of people used more than one service in a week

but, taking this into account, 3754 different people had accounts registered on central CUTE systems and there

were 4144 different accounts of which nearly 1600 were used on at least one system each week. During 1995

we have focused on improving the installation procedures for the different clusters with emphasis on providing

common solutions. This will be an important issue in 1996 as we will see changes in the operating system for

HP and IBM systems and we must reduce the time required to install and reconfigure our systems.

UNIX Work Group Servers

On the Work Group Server side, the rapid expansion of 1994 came to an end and few new machines were

added to the existing clusters. One of these was a new Work Group Server added at the end of the year when a

machine previously managed by TH division was moved to the Computer Centre to be managed by CN for the

users. (A second machine is to be moved early in 1996.) The user base continued to grow, however, and by the

end of the year a total of 1800 accounts were registered, an increase of 1000 over 1994. The number of users

active each week more than doubled from 300 to over 720.

UNIX Workstation Support

Once again the principal effort of the Division’s UNIX Workstation Support team was basic support of the

UNIX system software on the different UNIX-based platforms in CERN. The major area of expansion during

the year was X-terminals, mainly those from NCD and HP, and HP Workstations. The Apollo/Domain service

was run down and finally closed at the end of the year. Several of the CERN-written UNIX user guides were

updated and a guide to the services offered by the team was published.

The Andrew File System (AFS), has continued to expand and the filebase grew to over 300 Gbytes,

housing the user files of over 3000 users. There were nearly 2000 AFS client nodes on-site and a growing

number of clients of the CERN filebase off-site. As in previous years, HEP sites throughout Europe, and

indeed beyond, have looked to CERN to provide AFS tools and expertise, especially in the area of delegating

authorization for the various group administration tasks such as allocating and managing disk space.

The central print spool service was used by more than 600 printers across the site and a new version of the

Xprint tool was released which avoids individual users requiring to declare even a subset of these locally and,

therefore, greatly eases user printing from UNIX. The X-terminal service which assists users in the purchase,


installation and configuration of X-terminals has proved ever more popular, especially the scheme whereby we

purchase a small number of simple X-terminals at regular intervals which CERN users may buy from us for

urgent needs.

OpenVMS Services

The VMS service continued to remain popular with a steady number of over 2000 users per week. In 1995

the service underwent further rationalization. The VXENG cluster, consisting of mainframe-style hardware

was switched off and the users moved to dedicated workstations in the central VXCERN cluster. A diskserver

was added to the cluster to provide symmetric disk access to all cluster members.

General Services

DXCERN continued to provide a faithful service to a user population of about 200 per week and several

hundreds per month. The news service, DXNEWS, has almost doubled its number of client machines to

around 1000 per week and had to cope with a news volume of around 700 000 incoming news articles per

week, an increase of about 50% over the previous year.

A new mail server was introduced in 1995. This server is used as a postbox for storing users’ incoming

mail and can be accessed from any client computer using the IMAP or POP protocol. It has also allowed the

use of obvious mail addresses of the form [email protected] for both incoming and outgoing mail.

The ASIS application software service has become, more than ever, an essential part of the CERN UNIX

environment. This repository contains a large variety of software installed and maintained by many different

people. The dependency of the UNIX service upon it has meant that work continued to automate the

procedures for installing and updating software, both to help the software maintainers and to minimize the

problems caused by system or human error. The repository was also very much appreciated by the HEP

community off-site; several HEP sites in Europe mirror the repository locally and an average of about

10 000 files a week were copied off-site via the ftp service.

The involvement with the World-Wide Web promotion and development was wound down during the year

as the activities and people involved moved to MIT and INRIA. However, we are still running the ‘original’

WWW server called info.cern.ch which is referenced in many books and articles.

In the area of server operations, there has been close cooperation with the operations staff to develop tools

to help in the daily running of the Computer Centre, particularly in the provision of a database of machines

installed and in access to operations guides. Work has also been done in collaboration with Operations and the

CORE service to evaluate commercial alarm systems that could replace our current home-grown software.

Consultancy and Accounting

The User Area in the Computer Centre was rearranged and a number of PCs and X-terminals installed for

users. The very popular Computer Book purchasing service was greatly expanded with many more titles for


sale to CERN users. There was a review of the accounting service with a view to modifying the data produced

and published to keep in synchronization with the changing environment of the central services.

Problem Reporting System

During the year a public-domain problem reporting scheme was adapted for use with electronic mail and

the World-Wide Web. The intention is to feed incoming mails to standard support accounts directly into this

tool and then allocate these problems to appropriate individuals for solving. This is now in production for

UNIX Workstation Support and the scheme has been adopted by several other major CN services including the

UCO and the Program Library. |

Virtual Reality

The VENUS Project (Virtual Environment Navigation in the Underground Sites) is a CN initiative whose

task is to construct and maintain “Virtual Prototype’ models of the LHC sites and experimental halls. These

models are extracted from the original CAD assemblies and allow engineers and designers to ‘fly through’ the

future premises and equipment, either on screen, or using Virtual Reality navigation equipment. VENUS

Virtual Prototypes are provided to the world-wide HEP community over WWW, using an in-house developed

3D browser called ‘i3D’. This tool allows visual integration of the distributed design of the machine and its

detectors, by associating hyperlinks to each 3D object. VENUS is also performing the Impact Study for the

surface sites of Point5 and Point 1, using 3D territory simulation, as well as preparing a 3D interactive

animation to simulate the whole assembly of the experimental halls, and helping to find optimal paths and

strategies.

Physics Data Processing

The CSF simulation facility was doubled in capacity with the addition of 20 low-cost Hewlett-Packard

workstations. With 45 processors, the CSF cluster continues to deliver well over 90% of its nominal capacity

each week. Integrated with the Computing Centre data storage infrastructure, users of CSF have access to the

full set of tape and disk services, extended during 1995 to include access to the AFS home directory file

systems used by the interactive services.

As described above, a new general-purpose public service, known as CERNSP, was opened on the IBM

SP2 system installed at the end of 1994. This is a scalable parallel system: a set of 65 computers

interconnected by a special embedded network providing high-bandwidth communication between nodes

without the heavy overheads and delays normally associated with local area networks. The processors of the

SP2 are organized in a small number of logical partitions to provide four related services: an interactive UNIX

service, a batch service, a parallel computing environment, and data storage services. CERNSP is the

successor to the CERNVM mainframe service, and is therefore available to all users and collaborations, with

batch and storage resources managed by the COCOTIME committee. At the end of 1995, the operation of the

PaRC engineering service, provided on IBM workstations and an SP1 computer, was merged with CERNSP.

The CERNVM mainframe service is now scheduled to be stopped in mid-1996, and was further downgraded

at the end of 1995 with the removal of half of the processing capacity.


The SHIFT service, providing balanced computational and data access performance primarily for DST

analysis and event reconstruction, continued to expand in 1995 in line with the requirements of the LEP and

LHC experiments. A large facility was also added for the NA49 Collaboration, including support of the very

high capacity SONY DIR1000 tape drive and robot to enable processing of the experiment’s raw data. There

are now about 4 Tbytes of disk storage available to applications.

The Meiko CS-2 parallel computer, funded by the European Commission GPMIMD?2 research project,

was expanded in size and now has 64 powerful SPARC processors. The CS-2 has been used by a number of

experiments during the year, and has become the main data processing facility for the NA48 experiment,

including a novel application in the form of parallel data recording and reconstruction. This was demonstrated

during 1995, and will enable the relatively high data recording rates (up to 20 Mbytes/second) to be handled

when the experiment starts running in 1997. CERN’s participation in the GPMIMD2 project was again

positively reviewed by the EU, and funds have been allocated to double the size of the CERN CS-2 prior to the

end of the project in 1996.

Two new high-density magnetic tape products entered production during 1995: the DLT system developed

by Digital Equipment Corporation and Quantum, and the Magstar system developed by IBM. Both of these

systems are installed in new robotic systems, and DLT drives are also provided for manual operation. This has

enabled the migration away from low-capacity tapes to begin and, together with improved automation, has

allowed the level of manual operation to be reduced. A project has begun to automate fully the tape service,

with the acquisition of additional robotic tape handling equipment through an open tender process.

During 1995 several experiments, including OPAL, DELPHI, NA48, CMS and the ATLAS test beam,

began recording raw data directly on magnetic tapes in the Computer Centre. The experience was successful,

and provides collaborations with access to a wide and evolving range of tape media and automation

equipment.

1995 saw the first introduction in the Computer Centre of HIPPI standard high-performance networking

equipment. It was successfully used to interconnect large Silicon Graphics computers to each other and to the

IBM SP2. HIPPI will replace the five-year-old proprietary UltraNet equipment in applications which require

more bandwidth than is available using the more conventional FDDI standard. At the end of the year, a Netstar

Gigarouter was installed which will act as a high-performance switch interconnecting the FDDI and HIPPI

infrastructures.

A project was begun to study the relevance of true ‘commodity computing’, Windows/NT and the Intel

PentiumPro chip, as a platform for physics data processing. A number of large physics programs have been

successfully ported to this environment and encouraging benchmark results obtained. A small configuration of

PCs has been integrated into the standard CORE computing environment and reliability studies are now under

way.


Computing for Engineering

Digital and Analog CAE/CAD Support

The Sun Computer-Aided Engineering cluster, comprising 75 workstations and two central servers for the

storage of applications and home directories, now accommodates a user community of 340 registered users.

Originally, the customers of the Sun CAE cluster were mainly from the ECP Division. Today, however, 40%

of the users are from PPE Division, 30% from ECP Division and 20% from the Accelerator Divisions. To cope

with the new users and their requirements, more memory and more disks had to be added to the central servers

and two Sun servers were installed for logging in via X-terminals or logging in from PCs using an X-terminal

emulator.

With the increase of new users the Cadence CAE tool and component library support is still in heavy

demand. The usage of the different PLD/FPGA synthesis and design tools, especially together with the

Cadence tools, has also increased. Support continued for the Exemplar and Abel synthesis tools and the Altera,

Xilinx, Actel and OrCa FPGA design kits. During the year, the following new tools were installed on the CAE

Sun cluster: a new FPGA design kit for the Lattice FPGA family and VISUAL, a graphical Hardware

Description Language entry and debugging tool using block diagrams, state machine diagrams, flowcharts and

truth tables. The licensing of the MATLAB tool suite is now centrally administered. For technical training

several courses and technical seminars were organized together with the major tool and FPGA suppliers.

The number of LabVIEW licences grew to 120, of which 50 each were for Macintosh and Windows, and

20 for Sun or HP-UX. The collaboration with JINR on LabVIEW is well established. A laboratory area for

hands-on help to users with practical problems is in preparation.

Saber and PSpice support continued to be provided to the growing community of analog CAE/CAD users.

Effective assistance for these powerful tools is vital during the design and construction of the LHC and its

experiments, as it allows designers to optimize equipment for performance and reliability, and to cut

development times by avoiding many expensive hardware prototypes.

A one-man-year effort was invested in the creation of Mast/Saber power semiconductor models to help

simulate LHC power converters and the LHC beam dump facility. New modelling work, involving power

converter transformers, accelerator beam monitors and the gas system for the ATLAS muon detector (a

hydraulic Saber application), has also begun.

The year was highlighted by the evaluation and introduction of the Maxwell SI Eminence code, a suite of

electromagnetic field calculation tools with emphasis on electronic Signal Integrity (ST) and ElectroMagnetic

Compatibility (EMC). Good initial experience has been gained with modelling and analysing microstrip and

straw-tube type particle detectors, and with extracting SPICE simulation models for interconnects of high-

speed electronic systems.


Microprocessor Support

Considerable effort went into putting information on the World-Wide Web with the intention to use the

Web as a primary means of support.

A new revision of OS-9 (V3.0) was evaluated and is ready for use by the LEP and other experiments. Work

with Microware’s new C++ compiler that follows ANSI standardization documents was started.

For LynxOS, the major changes were the introduction of version 2.3 on existing hardware platforms: i386/

486, MC68k; and the addition of a new, PowerPC-based hardware platform: PowerPC 603/604. LynxOS

software can now be installed over Ethernet from a file server.

A large conference, Open Bus Systems "95 (Zurich), was jointly organized with Active Exhibitions Europe

and VITA (VMEbus Implementors Trade Association).

A new release (V4.0) of NuThena’s tool for modelling and simulating time-dependent systems, known as

Foresight, was received, together with versions for additional platforms and operating systems (HP, Solaris

2.4). A training course was given. The release version of a C-code generator was installed and a pre-release

version of the VHDL-code generator was tested. A second joint project with NuThena was launched.

A workshop on VMEbus Extensions for Physics was jointly organized with ECP Division, and the results

have been followed up.

Mechanical Engineering and Related Fields

1995 brought an increase of almost 100% in the LHC experiments’ use of mechanical and electrical

CAD-—-the principal CAD package in this domain, EUCLID, has been in use at CERN for over a decade. At

present the distribution of EUCLID use in the Divisions is as follows: 40% EST, 40% PPE—mostly for the

LHC experiments, ATLAS, ALICE and CMS—-and 20% ST.

A major change for EUCLID users has been the workstation switch from VAX/VMS to DEC-ALPHA

(250 4/266) running UNIX. Forty-nine ALPHAs replaced 35 VAX seats bringing additional capacity to cater

for new EUCLID users. The use of a mixed-system database-server has been a great help in EUCLID’s

ongoing changeover from one operating system to the other.

Yet again Structural Analysis, Magnetic Field Calculations and Accelerator Simulation Studies had to have

more computing power. The original eight IBM RS6000s of the PaRC project are being replaced by eight

SP2 nodes of CERNSP. PaRC’s existing eight SP1 processors will be connected to CERNSP. This move will

create a homogeneous system whilst doubling the power available.

The growth of LHC collaboration activities increased the need for data transfers between mechanical CAD

packages, and data transfers to the VENUS world of Virtual Prototyping are also regularly needed. The

Computer Aided Detector Design (CADD) team helped in this important data transfer work and also made a

solid contribution to the specification of an Engineering Data Management System (EDMS) which is to be

acquired by CERN. This EDMS will be used to manage all engineering information (specifications,


production drawings, technical documents, etc.) for the LHC and its experiments over the complete life of the

project.

PC-Based Engineering Tools

During 1995, the Division offered increased support for Engineering software running on the IBM PC

compatible platform, particularly in the AutoCAD area, but in addition many new items of software were

tested and some of them were installed for general use at CERN. Examples are AutoCAD version 13, P-CAD,

Altera, LabVIEW, Mathematica, MathCAD and MatLAB.

Tests were carried out on a new system for handling CDs over the Novell network. The equipment had four

readers and could handle a total of 250 CDs. It was foreseen to use the system for less frequently accessed

titles, complementing the existing CD-ROM server. Owing to software problems it was not possible to install

it on a production basis, but it is planned to further investigate this area in 1996.

An evaluation of new European PC hardware was carried out in collaboration with AS Division, with a

view to introducing a second approved supplier in this important area. New standard graphics and sound cards

were also successfully introduced for all new high-end PCs at CERN.

The collaboration with the St. Petersburg Institute for Nuclear Physics (PNPI) continued with the

development of an updated version of PC-BANK to handle 32-bit components. PC-BANK is a component

database for P-CAD which is running on the NICE servers using a link to an Oracle data base. In collaboration

with the ECP and PS divisions, the database’s contents were significantly improved. A new Windows program

called PC-LIST, for automatic parts list generation from PC-BANK data, was developed.

Progress was also made on commercial and technical issues related to AutoCAD where a new maintenance

and support contract was placed with a UK supplier. As part of this arrangement, AutoCAD version 13 will

shortly be introduced as a fully floating licence system for both DOS and Windows versions of the product.

Central Database Support

Throughout the year, we continued to offer support for the various Oracle servers operated by CN for the

general Oracle service and also for several nodes for the SL Controls Group and AT Division. In particular, the

SL nodes underwent major changes. The logging system was upgraded and a disk RAID array was installed.

As well as logging data from the SPS and LEP, it now also logs data from the LHC Magnet String tests being

conducted by AT Division.

Measurements of performance of the parallel processing version of Oracle have shown significant gains in

response times for database manipulations. As part of the preparation for the closure of CERNVM, Oracle

tools were successfully deployed on the CERNSP. A second generation of GUI client tools, including a

powerful CASE tool, were installed in the NICE environment. Preliminary evaluations and installations were

made of integrated WWW-Oracle server and client modules. SL Division was given significant support,

including the loaning of a database server, in order to cope with its large increase in the use of Oracle-based


data processing, used to collect measurement data from the SPS and LEP. Negotiations with Oracle for a

further extension of the existing contract were completed.

Application Software

Program Library

‘During 1995, the CERN Program Library switched from HEP-specific tools for code management and

installation to industry-standard ones. This involved a significant amount of work, but will bring

corresponding benefits in the future. Not only will the effort to build a new version of the library be

considerably reduced, but the new tools will be significantly easier to use for users and installers both at

CERN and outside.

A new activity, known as LHC++, was launched around the middle of the year and was focused on

understanding what the CERN Program Library might become for LHC-era experiments. As the name

suggests, the focus was on C++ solutions. Significant progress was made in a few months, and the framework

of the new strategy is taking shape. The main strengths of this strategy are the emphasis on standards—

de facto or de jure, plus the focus of CERN effort on HEP specific issues.

Further Fortran 90 compilers were installed on CERN platforms, and a version of the CERN Program

Library compiled under Fortran 90 was installed on the Meiko CS-2.

Object Persistency

The LCRB project RD45, to solve the problem of LHC event data VO, was approved. The goals of this

project are to find solutions to the problems of handling Persistent Objects for LHC-era events—essentially

the management of LHC event data. The focus has been on standards, and a widely accepted architecture,

based on the use of commercial standards-conforming Object Databases coupled transparently to Mass

Storage Systems, has been evolved.

Simulation

The major emphasis was on technical work of the RD44 project (GEANTA4) which aims at a re-designed

GEANT using Object-Oriented technology. The RD44 Collaboration has grown to some 70 scientists world-

wide. The milestones set for 1995 were successfully met: delivery of an Object-Oriented design for GEANT4

and a C++ implementation of a first prototype including geometry and tracking functionality plus muon

physics. From the performance and functionality obtained, there are clear indications that GEANT4 will be

the simulation framework for the next generation of HEP experiments. Support of the current GEANT (3.21)

continues and many current and future experiments have successfully used the feature of Boolean operations

in the geometry that it introduced; it is now considered to be a mature and stable product.


Data Analysis Techniques

The Physics Analysis Workstation (PAW) and the Parallel Interactive Analysis Facility (PIAF) data

analysis tools continued to be consolidated with improved Web documentation and more robust code. A new

PAW nTuple query processor entered the final stages of development. Improvements were made in the area of

graphics, most notably the introduction of a Z buffering algorithm in the HIGZ package. In addition, new

PIAF services were offered on the Meiko CS-2 machine (for the NA49 experiment) and on aDEC TurboLaser

machine (for the ALEPH experiment). As a vehicle for providing Windows 95 and Windows/NT versions of

PAW, a replacement for the KUIP user interface package was developed in Tk/Tcl.

Work began in earnest on investigating possible future data analysis tools. A decision was taken to develop

a prototype tool based on the Iris Explorer product. The Explorer tool was selected on account of its excellent

fit with the strategy for GEANT4 and graphics (Open Gl, OpenInventor, VRML).

Parallel Architectures

The year saw the Meiko CS-2 being well exploited by the application teams that had prepared for it. The

NA48 Collaboration used the machine very successfully for central data recording during a test run, the first

time this had been done at CERN. The data, once stored, were then subject to various analyses on the same

machine. Further work was undertaken on the potential of parallel architectures as part of second-level

triggering systems for LHC experiments. Finally, a parallel version of the GEANT simulation program was

used in production for two experiments.

Operations

The main activities during the year were the consolidation and further enhancement of those procedures

developed during the previous year. The online procedures for controlling equipment installations, logging

system activities, and displaying operational guides were essential for the smooth running of the new

computing services. The older services were not forgotten, and considerable effort during the second half of

the year centred around the further downsizing of the IBM mainframe running CERNVM. The change from

an IBM 3090/600)J to a /300J during the Christmas break went very well, and it is to be hoped that the final

disappearance of this machine in 1996 will go equally smoothly.

The number of computer systems running the many different CN user services is now fast approaching

400. The installation of these systems and their associated peripheral devices required careful planning to

ensure that not only floorspace was available but also that the necessary power and networking facilities were

available on the day of installation. This was successfully achieved through the online procedures which

interface to the network and equipment databases at present.

Many of those 400 systems run in parallel to provide specific user services like the CORE and SHIFT

facilities but each in the end needs to be independently monitored and each can cause an alarm requiring

operator response. While there is a total of 150 display screens in the centre, not all of these have to be looked

at to ensure all is well. Locally developed procedures like the COMS network monitor and the CNSURE


system monitor localize the alarms in the operators’ control room. These, however, lack some functionality

and as a result the commercial product Spectrum is currently going into service to monitor the networks, and

the search continues for a more encompassing systems monitor. In view of the ever-decreasing personnel

numbers it is essential that all system monitoring be handled automatically.

Networking

The internal networks ran well throughout the year, now being based on about 150 Ethernet local area

networks interconnected by a switched FDDI backbone with a theoretical total capacity of 1.5 Gbit/s. First-

line maintenance of this service has been outsourced for several years, and a new contractor was selected by

call for tenders during 1995.

Work on the internal networks was dominated by the structured cabling and routing project, which aims to

completely modernize the networks before the end of 1997. The main contractor, Olivetti Oliservice,

completed about one-fifth of the total project during the year, comprising 10 star points containing about

4000 network outlets, and installed about 1000 user devices. Contractors were also appointed for the optical

fibre infrastructure (Gity and Nokia Kabel) and for the supply of network routers (Olivetti and Siemens). In

particular, the industrial cable management package provided by Olivetti was further developed to provide

management tools required by the operation of the structured cabling as well as the management of the fibre/

coaxial backbone and services distribution of the new routed infrastructure.

A great deal of work was needed by CERN staff in support of these contracts, both in preparation for the

installation work and in setting up operational procedures for the new infrastructure. A major effort was made

to modernize the networks within the Computer Centre, to match the requirements of distributed client/server

computing. A complete plan was developed for the migration of the networks from a ‘bridged’ to a ‘routed’

topology, and its implementation was started. Also, a World-Wide Web interface was made available for users

needing to check the status of their network connection or to request modifications. This is linked into

databases and other tools used to manage the networks, all of which required intensive adaptation. In

particular, the industrial cable management package provided by Olivetti was further developed to provide

management tools required by the operation of the structured cabling as well as the management of the fibre/

coaxial backbone and services distribution of the new routed infrastructure.

The industrial network management system selected in 1994 went into operational use. Other industrial

network monitoring devices were evaluated, and a doctoral student developed additional management

software for local needs.

Some effort was devoted to evaluations of future technology. A search was started for Ethernet switches

able to support multimedia traffic. Earlier laboratory tests evolved into a pilot local ATM network, with

equipment from several companies, successfully running Internet software. A particular success was a test of

ATM running at 155 Mbit/s over copper cables.

In external networking, 1995 was an extremely busy year, with major changes in Internet service

provision, especially transition from Unisource to BT as the service provider for the DANTE Europanet

service. CERN constituted a consortium for Internet connectivity to the US with the US physics community,


IN2P3, the UN International Computing Centre, and the World Health Organization. Effort on Internet traffic

analysis has continued with almost complete automation of the data taking, analysis and WWW presentation.

CERN became an Internet eXchange Point, one of several in Europe, to which Internet service providers

can connect. CERN derives enhanced connectivity and quality of service from their presence. As a

consequence, CERN operates an Internet Multicast Backbone relay. This allows CERN to videocast events

such as ATLAS and CMS collaboration meetings, or LEPC and LHCC meetings over the Internet.

Improvements to the technology used are under way.

Operation of the main electronic mail gateway continued even though its role is less crucial than before.

The electronic mail-to-fax gateway is now a well-established service. The automatic call-back system for

computing from home grew to have approximately 1000 users. The DECnet service was very stable except for

a change to routing American traffic via INFN, and successful tests of DECnet applications over Internet

protocols augur well for the future.

The CEARN service, previously the heart of CERN’s EARN/BITNET connectivity, stopped prematurely

due to a hardware failure, after a decade of service, the service being taken over by the CERNVM mainframe.

As usual, the detailed coordination of external networking with many other sites and with multiple service

providers led to a high level of essential travel and meetings.

1995 CERN School of Computing

The eighteenth CERN School of Computing took place in Arles, France, and brought together 22 lecturers

and 68 students from 17 different countries and of 21 different nationalities. The School was organized in

collaboration with the Institut National de Physique Nucl£aire et de Physique des Particules (IN2P3).

The lecture programme (47 one-hour lectures, supplemented by tutorials) was varied and was greatly

appreciated by the students. The School was heavily oversubscribed and a selection of students had to be

made. The Proceedings were published as aCERN Report in October.

Technology

CAD Data Transfer

Contact with the ProSTEP company and Association was maintained; a test version of the PS_Caselib

toolkit and an update of the Neutral File Adapting System (now called PS_IGES adapter) were obtained. The

CADD file exchange server was made available for engineering firms acting as sub-contractors to CERN.


AutoCAD

Owing to the extensive networking possibilities at CERN and the large installed user base, various

evaluations of network usage and licence monitoring schemes for AutoCAD were carried out together with

AutoDESK. This has now resulted in a commercial product. CERN also regularly participates in beta-

evaluation sessions for AutoCAD and associated programs.

Accel Technologies

CERN is currently collaborating with Accel Technologies and is participating in a beta-evaluation of a

Windows-based version of its P-CAD software. CERN has a large number of licences for the DOS-based

P-CAD product, which is used for schematic capture and printed circuit board design.

Power Semiconductor Modelling

Semiconductor models required for the simulation of the LHC power converters were created in

collaboration with Analogy Corporation. The aim is to integrate these models into the library of Analogy’s

Saber analog simulator.

NuThena, Foresight

A new joint project was launched with NuThena Systems on bridging the gap between modelling/

simulating and implementing real-time systems. A first example was implemented in collaboration with PS

Division.

Testing of Microprocessor Hardware and Software

Field tests of LynxOS version 2.3 from Lynx RTS were done on Intel 486, MC68k, and the newly

introduced PowerPC-based platforms. FasTrak, a user-friendly development environment for OS-9 from

MicroWare, was tested and introduced for general use.

VITA, VSO, VIPA

The Division participates actively in VITA standardization efforts (VITA Standards Organization-VSO),

on the IP-Module mezzanine bus specification, and to some extent on the Embedded System Software

Environment (ESSE). Work was performed for the ‘Recommended Practices’ document for VMEbus in high-

energy physics, within VIPA, the VMEbus International Physics Association.


ATM and Multimedia

CERN concluded its involvement in the EU projects STEN and BETEUS via the Swiss Telecom ATM

pilot. This led to participation in several demonstrations including the RACE’95 Summer School. CERN was

solicited as a partner in several new project proposals, of which the EU approved a Telematics project dubbed

ATRE (ATM for Research in Europe) starting in 1996 with Alcatel, CISI, RENATER and the EU Joint

Research Centre (Ispra). The emphasis is on packet video applications, i.e. remote collaborative working

including video-conferencing, which fits very well with the needs expressed by the LHC experiments.

The Geneva-MAN project (155 Mbit/s ATM-based Metropolitan Area Network) linking major

International Organizations in Geneva plus the University of Geneva, was successfully launched, being

inaugurated during the massive Telecom95 exhibition and conference. Several CERN staff were involved in

various ways in Telecom95.

Internet

CERN staff participated in the Internet Engineering Task Force, and a staff member was elected Chair of

the Internet Architecture Board, a senior committee in Internet affairs. CERN staff helped to launch the

Geneva Chapter of the Internet Society.

ODMG

CERN is actively participating in the Object Database Management Group (ODMG;), which has developed

a standard for Object Databases, together with a number of language bindings (Smalltalk, C++, OQL, ODL

and, soon, Java). Release 1.2 was published at the end of 1995, and release 2.0 is scheduled for mid-1997.

HEPIX

HEPIX (HEP UNIX) is an organization which groups together UNIX system admininistrators and service

providers from the world’s major HEP laboratories and institutes to discuss and develop methods, procedures,

and tools to make the UNIX environment presented to physicists more uniform across HEP sites as well as

easier and more comfortable to use and understand. It channels its activities through bi-annual meetings and

specific working groups, and the Division has played a very active role in these. The most notable examples

are the HEPIX X11 group which has produced a complete user environment and the AFS working group. CN

Division also provides the current chairman of HEPiX.


Accelerator Technology Division

In their technological domains, the Groups in AT Division carried out, as usual, CERN-wide activities for

maintenance and operation of machines and experiments, and were strongly involved in LEP2 and LHC R&D

projects. In the second half of the year a considerable effort was made by the management of the Division in

collaboration with the staff to prepare the transition towards an LHC Division centred on LHC core activities.

Cryogenics

Cryogenic Support for Physics Experiments

Cryogenic support was provided to eight experiments using superconducting detector magnets (NA44,

NA45/NA55, NA47, NA49, RD5, OMEGA, ALEPH, and DELPHI). The cryoplants associated with these

experiments totalled 40 000 hours of running time. Owing to improved reliability of utilities, downtime

dropped from 0.3 to 0.2%. Downtime due to direct failure of cryogenic components remained unchanged at

0.03%.

Demand for cryogenic engineering support to the LHC experiments ATLAS and CMS is rapidly

increasing. Participation in the design of cryogenic systems and test facilities for these detectors will constitute

a major part of CERN cryogenic activities in 1996.

Work on the cryogenic system for the NA48 liquid-krypton electromagnetic calorimeter continued in view

of the planned commissioning date in 1996. The last of a series of prototype runs, which had extended over

several years, was completed in September 1995.

Three liquid-hydrogen targets were in operation for PS and SPS experiments.

Cryogenic Support for LEP

Following the installation of superconducting cavities at points 2 (4 modules), 6 (8 modules) and

8(4 modules), a further two of the four large 12 kKW/4.5K plants started cryoproduction for LEP2.

Performance and reliability are very good. The last of the four 12 kW/4.5 K plants is ready for operation with

cavities to be installed at point 4 in the spring of 1996.


Cryogenic systems associated with the superconducting cavities for accelerating electrons and positrons in

the SPS for injection into LEP continued to perform well and allowed a novel (400 MHz) LHC cavity

prototype to be tested in the SPS.

The superconducting quadrupole magnets of the low-ß insertion at LEP point 6 were connected to and

operated with the new LEP2 cryoplant, and the connection at point 2 is under way, thus freeing two smaller

plants for installation in experimental areas. Work started on the extension of the liquid-helium distribution

systems at points 2 and 6 to meet the requirements of LEP2 Phase IV. Large helium storage vessels were

ordered from industry after detailed studies of the needs of LEP2 and the LHC.

Industrial Services for Operation and Maintenance of Cryogenic Systems

A contract was placed for progressively passing responsibility of cryoplant maintenance and, later on,

operation to an industrial consortium; first experience is being gained in this novel form of co-operation with

industry.

Cryogenic Activities for the LHC

Important modifications to the LHC cryogenic system were introduced in 1995, namely:

— the number of cryogenic feed stations around the LHC ring was reduced from eight (at all eight

intersection points) to four at the four even-numbered points which house the LEP experiments and the

LEP2 cryoplants.

— the principle of housing all helium lines in the magnet cryostat was abandoned in favour of an external

cryogenic distribution line. The external line allows larger pipe diameters to be used. This is essential

for implementing fourfold symmetry not only for the 4.5 K, but also for the 1.8 K helium circuits,

which otherwise would have required cold compressor stations at all eight points. The external line

gives greater flexibility for the installation programme, but efficient and economic design of such a

system is a major challenge for cryogenic engineering.

An intensive magnet test programme was undertaken, using both the individual-magnet and the magnet-

string test facilities of hall SM18. Both activities, together with the tests of superconducting cavity modules,

put a heavy load on the SMI8 cryoplant. Several upgrades were undertaken to meet all requirements. The

cryoplant was equipped with an online helium purifier to increase its availability for quench tests (more

than 100 such tests took place during the year) and an auxiliary precooling stage was installed to double the

performance in the liquefier mode.

Other tests to validate and optimize LHC design concepts concerned cryostat components, pressure relief

valves, thermal insulation techniques, cold helium compressors (two prototypes developed by industry were

tested), instrumentation (industrial calibration techniques for high-precision cryogenic thermometry), etc.

Cryoplant process engineering studies were also pursued.


Maenets

Existing Accelerators

At the PS, in addition to the general overhaul of several magnetic elements, three dipole magnets for beam

transport and two solenoids were constructed. Radiation-damaged pole-face windings were repaired. A

wiggler magnet was assembled and installed at the CLIC Test Facility.

For the SPS, the programme of refurbishing the SPS magnet coils is well under way. New spares are being

constructed in industry and several magnets were reconditioned. Investigations on mechanical movements of

excitation coils were made and as a result new packing shims and wedges are being procured. Reconstruction

of a number of beam transport quadrupole magnets was started and orders placed with industry.

To improve further the definition of the LEP energy, two NMR probes were installed in main ring dipoles

in the arcs near points 4 and 8. Another pair of NMR probes are ready to be installed near points 2 and 6

during the winter shutdown. The system for the modulation of the field in the LEP lattice quadrupoles was

extended into the two half-arcs around point 8. For the bunch-train programme the skew quadrupoles were

repositioned, and four of the eight ‘pretzel’ sextupoles were modified into skew sextupoles and relocated to

provide the possibility of controlling the tune split. LEP2-related work included the moving of quadrupoles

and the installation of new superconducting quadrupoles at point 6.

LHC

Detailed tests and measurements of three 10 m long twin 50 mm aperture dipole magnets were made,

including thorough studies of the dynamic behaviour of the field components as a function of the excitation

cycles. The last two dipoles of the first generation with structure variants were completed in industry. At the

end of the year they were being assembled into their respective cryostats. A new dipole design for 194 mm

interbeam spacing, incorporating improvements gathered from the experience on long and short models, was

completed and all components for two 10 m long dipoles were ordered. The new superconducting cables for

these magnets were developed and delivered, and the first set of coils were wound in industry by the end

of 1995.

A new order for 9 tons of superconducting cables was placed with four European firms. In this order, the

follow-up procedure and the quality assurance programme was established in agreement with the suppliers in

view of mass production. An intensive R&D programme is being pursued to measure and qualify the

parameters relevant in the interstrand resistance: type of coating, thermal cycles and pressures. The aim is to

guarantee in the LHC dipole an interstrand resistance higher than 10 uQ2, a value which has been obtained in

several magnets without prejudice to the performance.

The work on a 15 m long dipole developed in the framework of a collaboration with INFN progressed with

the procurement of all the necessary tooling and with the manufacture of a first dummy coil. An additional set

of collared coils for a second 15 m long dipole was also ordered, and the extension of some of the CERN

tooling to adapt them to the new magnet length has been started.


Tests of the new dipole magnet design are proceeding satisfactorily at the short model facility. Two coil

variants wound with the new 15 mm wide cable and an all polyimide insulation were assembled in the Coil

Test Facility and successfully tested. In the framework of the short model dipole programme, two

collaboration agreements came to very successful conclusions with the test at CERN of the model magnets:

— the single-aperture dipole wound with Nb3Sn superconductor and built at Twente University in a

_ CERN-FOM-NIKHEF-UT Collaboration reached 11T central field at 4.2 K without training, thus

establishing a new world record for dipole magnets;

— the twin 56 mm aperture model magnet, built at CERN in a CERN-Finnish-Swedish Collaboration,

reached 10.5 T central field after only seven quenches and all quenches after a subsequent thermal

cycle to room temperature were above 10 T, also a record for dipoles wound with NbTi superconductor.

As can be inferred, the test facilities both for long and for short magnets operated at full capacity all

through the year to provide essential information for the final steps of the R&D programme. In the short

magnet test facility 17 test runs were completed during the year, while two 10 m long dipoles were tested at

the long magnet test facility in hall SM18. |

The work on insertion and corrector magnets also gained momentum. The first test of al m model of a

70 mm single-aperture low-beta quadrupole achieved a gradient of 190 T/m at 4.5 K after one training quench.

A second prototype of a combined sextupole-dipole corrector was built in industry and tested. A prototype of

the correction sextupole to be installed at one end of the dipole units was successfully built and tested. A

correction octupole was also successfully developed and tested.

Important contributions were made to the completely revised design of the LHC cryostats with separated

cryogenic lines, taking into account the results of the test made on the Cryostat Thermal Model, also designed

and procured by the Group. |

In addition to the work on magnets proper, the Group has also developed a current lead made with high-

temperature superconductor (HTS) to power the orbit corrector dipoles. Compared to classical current leads,

the new leads have the advantage of a much simpler installation (no need for gas cooling) and a reduced

cryogenic load. A prototype, initially developed for about 100 A in normal operation, was successfully tested

up to 600 A. In parallel a collaboration has been launched with an industrial company to develop high-current

(13 kA) HTS leads.

The design of the LHC insertions progressed substantially: the design of resistive twin-aperture

quadrupoles for the beam cleaning insertions advanced well, and an appropriate layout was found for lodging

both the RF and a possible experiment at the same interaction point.

In the second half of the year, the LHC Test String was extended by the addition of a third 10 m long dipole

and was then successfully run, providing important information on the cryogenic and electrical behaviour of

long dipole magnets connected in series. The Magnet Group took full responsibility for the electrical and

quench protection aspects.

The quench protection of the LHC dipoles wound with the new 15 mm wide cable, was qualified during

series of tests performed on two short models. A new series-production technique to manufacture quench

heaters was developed with industry and successfully tested in the short model dipoles.


Prototypes of radiation-resistant bypass diodes for the protection of lattice quadrupoles and dipoles were

developed in collaboration with two European firms and successfully tested at CERN.

A preliminary design of resistive magnets for the SPS-LHC beam transfer lines was completed,

‚confirming that conventional magnets with copper coils are the most economical solution.

Vacuum

PS

The annual shutdown was used to implement important improvements for the vacuum of the various

machines—improvements primarily aimed at low pressure for operation with lead ions. For an urgent

replacement of several leaking vacuum bellows on one of the large and radioactive tanks of the PSB an outside

firm providing customer-specific machining services was engaged with full success.

In the framework of operation with lead ions, the PS average pressure was improved from about 1.1 E-8 to

3.4 E-9 mbar by the addition of 108 titanium sublimation pumps. The operation of these pumps is supervised

by an automatic control program which fires the titanium filaments for optimum vacuum performance. A new

man-machine interface for a unified vacuum supervision of the different machines, including the SPS, was

implemented and has become operational.

SPS

The year 1995 was one of routine operation in which the vacuum showed perfect performance, only

interrupted by a few short interventions necessary to replace leaking vacuum chambers in dipole magnets

provoked by mechanical fatigue.

LEP

The main vacuum-related activities for LEP were the layout modifications imposed by the change of

operation from the pretzel scheme to that of bunch trains, and modifications in view of LEP2. During the

annual shutdown, again more than 7km of the machine were opened to atmospheric pressure and

subsequently recommissioned for UHV operation. The vacuum system in the RF sections was modified and

the cabling prepared so that additional superconducting modules could be installed in several short machine

stops during the year.

The programme of improvements to the experimental vacuum chambers for LEP2 continued with the

modification of the OPAL vacuum chamber which was equipped with background masks and beam pipes of

enlarged section extending from about 30 to 60 m on each arm of point 6. As part of this programme a set of

fixed-aperture and movable-aperture collimators was installed. Similar modifications were prepared for all

other experiments and the necessary vacuum chambers, background masks, and photon absorbers were

manufactured and are ready for installation.


In view of LEP2 operation, systematic measurements were made on vacuum elements (bellows) near

superconducting modules to determine higher order mode power dissipation and cooling requirements.

The vacuum work related to the installation of superconducting cavity modules continued at points 2,

6 and 8. A superconducting niobium sheet module, rinsed with the high-pressure water jet, exceeded the

nominal performance during the high-power RF tests and was installed at point 2. A clean and dust-free

laminar flow assembly cabin was commissioned and 100 couplers were prepared for the RF tests. An in situ

bake-out of the coupler windows is now applied routinely to all modules before the high-power test. This leads

to a considerable reduction of the forming time.

Superconducting modules were installed in the high-power test facility at a rate of two per two weeks; in

parallel, the preparation of the accelerating units proceeded at a rate of one unit per week. Orders for vacuum

components for LEP Phase IV were placed.

A new contract for industrial services covering CERN-wide needs for vacuum work on accelerators was

placed.

LHC

First operating experience for the LHC was gained with the vacuum system of the magnet test string.

Detailed studies were started on the importance of the insulation vacuum for cryogenic losses, on the

measurement of pressure and gas spectra at different locations in the cryostats, and the propagation of a

simulated helium leak along the cold-bore vacuum system.

The detailed design of the beam vacuum system in the cold arcs was updated in accordance with the most

recent layout changes. A preliminary study of the vacuum systems in the injection and ejection regions, in the

experiments, and in the cleaning insertions was undertaken. An initial evaluation of cabling needs and rack

space in underground areas was also undertaken.

The design of the vacuum system for the SPS-LHC transfer lines using warm magnets was reviewed and is

under detailed study.

A major change in the design of the cold vacuum system of the LHC was the optimization of the beam

screen aperture from a square shape to a circular section, flattened at the top and bottom to accommodate the

helium cooling capillaries. New prototypes of this design complete with copper coating by a roll-bonding

technique, pumping slots and beam screen supports are on order from several firms. The understanding of the

physics of the cold vacuum system with synchrotron radiation induced desorption from cryosorbed gas was

extended with measurements both at CERN on the EPA machine and at Novosibirsk on the VEPP-2M storage

ring as part of aCERN-BINP Collaboration.


Cooling and Ventilation

Changes were made to the magnet water cooling circuits in two LEP sectors to cope with the increased

LEP2 energy. New air compressors were installed at points 2, 4, 6 and 8 for the cryogenic installations.

The programme was begun for the conversion of 10 large refrigeration machines to adapt them for use with

refrigerants which meet the new international environmental standards. One machine was successfully

converted during the year.

Contracts were awarded for the project to dehumidify the treated air supplied into the Jura sector of the

LEP tunnel. This system is to be installed in the 1995/96 shutdown.

Controls of air handling units are being progressively adapted to the future LEP2 operation. The full

commissioning of the Local Supervision system based on LabVIEW was achieved for all cooling and

ventilation processes, representing 30 000 points of measurement at each of the eight points of LEP. This

system stores all data at one minute intervals, permits trend and failure analysis, historical replay, and process

optimization. The project is now complete and has reached the primary goal of improving the operating

efficiency of the HVAC systems serving the accelerator.

Design work on the LHC project continued and contributed to the determination of the outline civil

engineering requirements and the documentation for the ‘Etude d’impact’.

The preparation of the tender documents for a future CERN-wide Operation and Maintenance Contract

was slowed down by the restructuring of the Division.

Survey

Metrology of Accelerators

The 1994/95 shutdown campaign of levelling measurements around LEP still revealed regular movements

and deformations. This led to a smoothing refinement on about 70 quadrupoles in order to keep the vertical

dispersion within 0.15 mm r.m.s. The measurements repeated in December 1995 have shown that this tends to

be the yearly number of realignments necessary to maintain the geometry of the LEP plane. Hydrostatic levels

were installed in P2 (on both sides) for monitoring the low-ß intersection magnets. Radial measurements were

performed over almost four additional octants; these showed a significant degradation and 120 quadrupoles

were realigned in a first smoothing stage. For LEP2 and other programmes, various components were

positioned. A full survey of the PS followed by a bi-axial realignment to compensate for the deformations of

the girder was also carried out. Additional measurements and realignments were also made on TT10 and

TT60. The Neutrino line and the pits were also checked with a link to the geodetic network by means of

differential GPS measurements.


Metrology of Experiments

In connection with changes or maintenance work on fixed-target experiments, the main surveys and

alignments were made for SMC, OMEGA, CHORUS, NOMAD, NA48, NA49, NA50, WA98, PS195, PS202,

Crystal Barrel, OBELIX. Various secondary beams and test beams were also modified—mainly RD5, RD6

and RD34. As for LEP experiments, masks and new vacuum equipment were aligned in OPAL and DELPHI.

A new vacuum chamber was aligned in L3, on which the forward spectrometers were also fully surveyed.

LHC and CLIC

Preliminary studies are continuing for the metrology of the LHC (machine and experiments), together with

tests on the String and on the CMS bench. A more detailed design study was also started for the dynamic

alignment system of CLIC, in preparation of the CTE2 test facility. The new wire offset sensors were tested,

and another kind of special sensor was defined in collaboration with industry.

Industrial Controls

All the main hardware for the LEP2 Project is now installed and commissioned. Second-generation

software with the so-called “light objects’ was successfully implemented in both Sulzer/Linde and Air Liquide

process control hardware, providing smooth operation of the liquefiers. ‘Advant’, the new generation of ABB

hardware and software is currently being evaluated.

The LHC String Test Project has produced much data using the fast data acquisition system. This feeds

data into the Archiver, Transient recorder and Data Logger, all of which have been made operational.

Optics, Lasers, and Related Developments

The optics and lasers section had to ensure the reliable operation and maintenance of the synchro laser and

bunch train generation system for the CTF. In addition, the section was deeply involved in the Excimer Laser

Surface Annealing (ELSA) project which aims at improving the quality factor of the superconducting cavities

by laser annealing of the niobium film. A computer controlled optical system was built for the 1500 MHz

cavities and used in November with the excimer laser of the LAMEL Institute in Bologna.

Studies on ferroelectrics have been pursued in view of two applications: high-intensity switches and beam

neutralization.

Database Support

The Database Support team was heavily engaged in providing and testing a prototype Engineering Data

Management System (EDMS) for the LHC project using a MAD version of LHC, LHC Short Straight

Sections and PS Booster data to ensure the usefulness of the system. The team represents the Accelerator


Sector in the EDMS task force, which aims to acquire a replacement commercial package to provide similar

tools for information management by mid-1996.

Energy Technologies

The group made decisive progress in defining the possibilities of the Energy Amplifier (EA). In this hybrid

nuclear energy system, neutrons produced by spallation with a medium-energy (1 GeV) proton beam are

further multiplied in a subcritical fissioning assembly. The choice was made of the fast neutron regime, using

molten lead as a heat carrying and neutron diffusing medium. This has the advantage of being able to run

safely at multiplication factors of up to k= 0.98, allowing an energy gain G = 120, for extended periods of

time (typical burnups of 100 GWday per ton of fuel). It uses thorium as a fuel (with the advantage of minimal

plutonium production), but can also use practically any fuel (including waste from ordinary reactors). Since it

can run in closed cycle (recycling its own actinide waste), geological storage could be eliminated. There is an

intriguing possibility of using the EA to destroy the existing stockpile of weapons and civilian plutonium.

A milestone was achieved by the completion of a report on the ‘Conceptual Design of a Fast Neutron

Operated High Power Energy Amplifier’ which will be published in a Technical report of the ITAEA and is

already the reference in discussions of institutions worldwide, interested in this new field. An EA module is a

1500 MWth unit fed by a dedicated 1 GeV, 12.5 mA proton accelerator (a three-stage, sector-focused

cyclotron). A conspicuous feature is the use of natural convection to evacuate the heat produced in the core.

This makes it a passive device in which a proton beam is dumped and heat is extracted. No intervention is

necessary during the five-year burnup period and it could remain sealed as a non-proliferation safeguard

measure.

An experiment (PS211) on the ‘Phenomenology of Spallation Neutrons in a Large Lead Block’ received

the financial support of the European Union. It is now in preparation and will start running at the PS in

spring 1996. One of the intriguing goals is to exploit a novel possibility of using resonant cross-sections for

the incineration of the few very long-lived fission products (such as ””Tc, and 12°),


Mechanical Technologies Division

General

The trend observed in 1994 was confirmed in 1995: more and more work was carried out for the two main

CERN projects, LEP 200 and LHC, with a corresponding decrease in the other fields of activity. As described

below, the Division has played an important role in the design, fabrication, assembly, and installation of

components to cope with the very tight LEP 200 schedule while in parallel giving full support to LHC R&D

and supplying a service to the whole of CERN in the domain of surfaces and materials.

Engineering Support

LHC Activities

In 1995, the Division made significant progress in its various tasks related to LHC R&D.

The Division was very closely involved in the operation of the LHC test string. Specifically this concerns

the installation of a third dipole, the installation of a composite vacuum barrier and an additional self-

supporting quench pressure relief valve and the associated experiments, in particular for the qualification of

the design principles of the valve.

The design of the new short straight section progressed towards a final solution, in accordance with

the specification of the new LHC design report (Yellow Book): the four feed points version of the LHC, new

magnet length, separate cryo-feedline, etc. A large amount of the groundwork in preparation for the CERN-

CEA/IN2P3 Collaboration for LHC was done, thus laying down the lines of the French contribution to

the LHC project. The interconnections between LHC magnets were redesigned accordingly and validated

through extensive testing of a number of critical components such as interconnecting bellows.

The design of the new LHC dipole models with 15 mm cables was completed, the relevant tooling built,

and most of the components ordered, in collaboration with the Magnet group of AT Division. A new winding

machine was designed, specified, ordered and installed, and a new coil modulus measuring machine

commissioned. The main market surveys and calls for tender for the components of the 10 m long dipole

models were launched and some of the important orders placed. The conceptual design of the LHC dipole

magnet has continued. Studies of coils under tensile pre-stress and with end cages were undertaken and some

models tested. |


The support to the dipole development programme was re-enforced as far as the mechanical

instrumentation and measurements on models are concerned. A large amount of work was invested in the

development of new transducers and methods to measure magnetic forces and stresses. In addition, studies to

assess the mechanical properties of constitutive materials at low temperature continued.

New beam screen models for the LHC vacuum system were built for impedance and quench behaviour

measurements in order to validate the design. A collaboration with the Dutch laboratory NIKHEF was set up

(COLDEX) for the design of the equipment for a LHC vacuum experiment at cryogenic temperature in EPA.

This design was completed in 1995. |

The Division also participated actively in the feasibility study and cost estimate which led to the decision

to use a separate cryo-feedline. | |

The design of the support post system of LHC progressed: a thermoplastic injected version of this device

was built and delivered. This will be tested in 1996, and would seem to offer a cost-effective solution.

As far as the support to LHC experiments is concerned, a great deal of effort was devoted to establishing

the civil engineering frameworks in view of low cost optimization (CHEAP Committee).

Work continued on the integration aspects of the ATLAS detector: this included involvement in design

studies for various connections (cabling, gases, fluids) and supports, and the integration of CAD models from

various origins.

The feasibility of aCMS tracker assembly procedure by means of suitable robots was verified by prototype

simulation. In so doing it was established that CAD and robotics could be combined to optimize the assembly.

A hydraulic press design study was undertaken for industrial production of the ATLAS liquid argon

calorimeter modules. It should be completed in 1996.

The parameters of the heavy hoisting gear needed for the experiments were established. Specifications for

these facilities were drawn up.

Conceptual studies of vacuum chambers for ATLAS, CMS, ALICE and LHC-B were started.

It is worth mentioning the exceptional effort made during 1995 to create the methods and tools for the

LHC Project planning: a Quality Assurance Plan was almost completed, a scheduling tool was selected and the

appropriate procedures defined, a request was prepared for an Engineering Data Management system together

with a pilot test project.

LEP 200 Activities

The studies and production drawings for the vacuum system as well as the layouts needed for machine

modifications during the July and October 1995 technical shutdowns and the June 1996 shutdown were spaced

out over the year following the MD test results.


With the final design studies and production start-up of the BICHN collimators (fitted with Bhabha

detectors), the series of collimators needed for the energy upgrade (some sixty have been added since 1991)

was completed. The polarization measurements line was readjusted one last time.

Synchrotron radiation tungsten masks were displaced and realigned in DELPHI, new masks were installed

in OPAL while design studies for the same type of equipment to be installed in L3 and ALEPH were

completed.

Existing Machines Activities & Work Organization

Existing CERN accelerators need permanent active support from MT design offices. All the layout

drawings, completed in 1994, are continuously kept up to date for all running accelerators.

The drawings for the whole PS complex and the SPS ring and transfer lines are in 2D Autocad format,

whereas LEP layouts are made as 3D Euclid drawings. The level of accuracy permits the correct installation of

any equipment inside the ring. All this documentation is now accessible on the PC network, in a very well

defined tree structure: each PC owner can obtain a layout on his screen and produce a paper copy on a

reproduction machine.

In 1995, two modern printing machines were put into service: one AO size machine on the Meyrin site, and

one Al size machine on the Prevessin site. A continuous effort is being made by the Division to connect every

user within the Accelerator Sector to this facility.

In addition to computer files, each archived drawing is copied, by the automatic production of two

microfilms, stored for safety reasons in two different places. For this purpose, a special device capable of

storing around 200 000 microfilms has been bought and all the old paper drawings have been microfilmed,

allowing a considerable saving of space and improved storage.

The updated monthly follow-up of all studies in progress (time foreseen, time spent, engineer in charge,

budget code involved) shows that 250 different jobs involving 60 people for a total manpower of 90 000 hours

were carried out in 1995. With the invoicing system, each customer is aware of the cost of design studies and

consequently is able to include it in the project budget.

It is worth mentioning the design and procurement of a thin Kevlar window of 2500 mm diameter for the

NA48 experiment. This equipment is manufactured in Italy by a well-known aerospace firm and gives very

good vacuum performance. Mechanical tests will be made at the beginning of 1996.

Handling devices were used to replace defective parts in radioactive areas (ACOL complex, SPS neutrino

chamber). Specialized dedicated equipment was devised for some jobs (detector in the PS area). Tests of

industrial equipment for visual monitoring and shape exploration should follow in 1996.


Manufacturing Facilities Group

General

In 1995, MF workshops worked predominantly (- 90%) for the Accelerator Sector. The number of useful

hours totalled - 94 000 with a well-balanced distribution among the various technologies available such as

conventional, precision and CN machining, various sheet-metal forming and welding techniques, quality

control and metrology. The major contributions are listed below in more detail.

Contribution to LEP 200

In November 1994 the Division was assigned the responsibility for manufacturing 30 new extension tubes

for the superconducting RF cavities and the adaptation of 30 existing couplers. The very stringent

requirements for quality and delivery delay were satisfied, the material being delivered between January and

February 1995 in time for installation during the machine shutdown.

Following this series, the Division was involved in the production of a further 230 extension tubes: the

adaptation of 70 existing couplers and the manufacture of 160 new couplers; in addition auxiliary parts such as

waveguides, coupler cooling and polarization components were also needed. Constant attention to quality and

costs was required and 20 units per months had to be delivered starting in May 1995. The Division organized

the production so as to spread the large work load over all its resources: subcontracting, Buildings 100 & 904,

and PPE workshops. In order to reduce costs and prevent bottlenecks for critical techniques such as spark

erosion, electron beam and YAG laser welding with the new equipment that was put into operation in 1994,

new manufacturing methods suitable for a larger production series were also defined. This job is currently

proceeding according to plan. It is a good example of how to exploit the full CERN potential to carry out

multidisciplinary jobs requiring flexibility and urgency, and moreover representing a heavy work load and

requiring the integration of several CERN resources and technologies. In December 1995 the Division was

asked to manufacture a further series of 48 extension tubes, new couplers, and auxiliary parts for delivery by

mid 1996 to cope with LEP 200 Phase IV.

Other components were also manufactured for LEP 200, including five collimators and several stainless-

steel vacuum chambers, with large diameters up to 350 mm. Two of the collimators were urgently required for

installation during the winter shutdown, and were manufactured in a ‘crash programme’ between November

and December 1995. Two experimental vacuum chambers, for L3 and ALEPH, were modified in the 1995

winter shutdown, involving the dismounting, transport, machining, TIG welding in a clean room,

measurements and reinstallation within a very tight schedule of fragile components with a beryllium central

part. Other adjacent vacuum chambers were modified in order to insert a tungsten mask.

Contribution to LHC

Examples of contributions are:

— the orbital TIG welding and the mechanical assembly of several magnet connections for the String Test

in SM18 in summer 1995 following a tight schedule;


— the MIG welding of the cold mass for the MFISQ dipole in Building 927;

-— R&D work with the SM Group for the beam screen, involving a comparison of the TIG, laser, and

electron-beam welding techniques.

Other Contributions

ISOLDE required several targets in tantalum, involving machining, TIG welding under glove-box

conditions, and electron-beam welding.

In summer 1995 large stainless-steel sheets 0.5, 3, and 6 mm thick and 3 m long were welded following an

urgent request to supply the manufacturer of the end covers of the NA48 experiment.

A thin, radiation-transparent experimental vacuum chamber was assembled by microTIG for a

FERMILAB experiment in collaboration with INFN Genoa.

The spinning of a 1.5 GHz RF cavity for R&D for TESLA was also carried out in collaboration with INFN

Legnaro. A complete cavity was successfully manufactured without welds and tests showed the best RF

quality factor measured so far.

The 40 MHz RF cavity for PS-LHC was completed and RF tests were fully satisfactory. The copper anode

for copper plating was manufactured by the sheet metal working team. This is another perfect example of a

large job requiring the integration of several technologies at CERN and in industry. The Division has the

responsibility for the manufacture of two more 40 MHz cavities in 1996.

Several tests were made to optimize the manufacture of the internal structure of the RFQ-LIS. The job is

currently under way for completion by May 1996.

Finally, three 2-dimensional ‘snail’ superconducting RF cavities were manufactured for Chaos studies by

Darmstadt. This involved the CNC milling of niobium sheets following complex polar equations and the sheet

metal preparation of the cavities for electron-beam welding. |

A last example of activity for the Research Sector was the manufacture of prototypes of u-metal wire

baskets for Athens University. Once the prototype was accepted, an original solution was found for

manufacturing the series of several hundred baskets, requiring a large labour content, by subcontracting the

work to a penitentiary workshop.

Other Activities

The mechanical engineering Subcontracting Section was kept extremely busy with a total turnover

equivalent to 87 000 hours, more than double that of 1994. In spite of the considerable overload the Service

succeeded in maintaining a well-balanced return to the Member States.


The Free Access Workshops saw their machine tools occupation rate increase, thanks to the excellent

service offered both with well-maintained equipment and professional assistance provided by the staff in

charge.

The machine tools Maintenance Section, in addition to dealing with the normal operations of repair and

maintenance, successfully completed the second phase of the programme to modify the CERN machine tools

to conform with EU directives in matters of safety. The third phase involving all the Engineering Support and

Technologies Division workshops on the Meyrin site, is due to start at the end of February 1996.

Investments

The retrofit of the electron-beam welding SCIAKY equipment is still under way in Germany, for expected

installation in Building 100 by April 1996.

A special project (MT-13) was dedicated to the improvement of metrology equipment, with the following

outstanding actions:

— retrofit of the BATY SHADOMASTER for 2D high-precision measurements, particularly adapted for

laminations with complicated contours (e.g. laminations for LHC dipoles or quadrupoles);

— acquisition of instrumentation for the online dynamic parametrization of NC machine tools

(orthogonality, tilt, skew, movement inversion defects, etc.);

— replacement of the old (1975) laser interferometric measuring system for straightness, angles and

flatness measurements in ranges of 1 to 30 m and resolutions down to 0.01 mm;

— acquisition of a topography 3D measuring station, with resolutions better than 0.02 mm, for non-

contact quantitative surface and thickness control for all forms of coatings, measurements of roughness

and shape parameters in pre- and end-quality control of a manufacturing process.

Some minor investments included the retrofit of the IMEX guillotine and the purchase of a LISSE rolling

equipment with neoprene rollers allowing the precision rolling of tubes. Two MIG Synergic welding machines

were ordered: this technique allows easier and higher quality welds for large thicknesses, something of

particular importance for the LHC.

Surfaces And Materials Group

Contribution to LEP 200

The work load of all activities in the Surfaces and Materials group was very satisfactory in 1995, the major

user being the LEP 200 programme. The availability of specialized installations and competent personnel

allowed the group to make notable contributions to the work of developing superconducting niobium-coated

copper cavities. As well as developing and perfecting the niobium sputter coating process to achieve optimal

RF performance, the group contributed to chemical and electrochemical surface treatments of both raw

material used for cavity construction (copper and niobium) and of complete cavities prior to sputter coating.

Endoscopic inspection of industrial cavities with the dedicated Scanning Auger Electron Spectrometer

designed and constructed earlier by the group indicated that the preparation and handling of the copper surface


prior to niobium sputtering are the major difficulties in the production of superconducting niobium-coated

copper cavities. This endoscopic inspection instrument, which to the best of our knowledge is the first example

of applying sophisticated laboratory analysis techniques to large finished engineered components, has

therefore been extensively used to examine the residual contamination on the internal copper surface of

cavities prior to niobium coating. The surface area of a complete 352 MHz cavity amounts to some 6 m? and

the Auger analyser head can be positioned inside such a cavity under ultra-high vacuum conditions so as to

inspect any suspected defective area of this large surface. This device, however, only supplies information on

the morphology and elemental composition of defects. It was therefore a natural subsequent development to

examine how defects in thin superconducting niobium films could be eliminated and its crystallographic

structure modified so as to improve the RF performance. In collaboration with the AT Division an opto-

mechanical device was designed and built to apply laser annealing to RF cavities. The device called ELSA

(Excimer Laser Surface Annealing) is at present limited to 1500 MHz monocell niobium-coated copper

cavities with the aim of evaluating the full potential of the technique. The first cavities were treated at the end

of the year using an excimer laser (XeCl, 308 nm) in the LAMEL Institute, Bologna. The results are now

being evaluated.

The work load for LEP 200 also includes a large volume of work for the couplers and RF extension tubes.

In this respect major contributions in the fields of materials expertise and selection, chemical cleaning,

vacuum heat treatments, vacuum brazing and sputter coating were made for the components produced in the

context of the crash programme. This work will continue next year.

Contribution to LHC

Since the approval of the LHC, the group has received an increasing number of requests for advice and

assistance on materials selection and workshop processes. This covers mostly metallic materials selection and

associated welding processes, but it also extends to the selection and testing of epoxy resins and adhesives

suitable for low temperatures and resistant to high radiation doses.

Other Contributions

As in previous years, the group satisfied a large number of users from both the Accelerator and the Physics

Sectors on a daily basis in all the speciality fields of materials and surface investigations, surface treatments

and electroplating, vacuum brazing, vacuum degassing treatments and outgassing rate measurements, vacuum

deposition of thin films, development of high-definition photomechanical components, and special high-

purity gas and fluid systems.

Service Improvement

Most of the renovation work of existing workshops and laboratories has now been completed. In 1995 the

full benefit of the improved working conditions was felt in a number of areas. In the chemical and

electrochemical surface treatment workshop not only have the cleanliness and safety aspects been

considerably improved, but new technologies have also been introduced. A good start was made in developing

methods to electroform 3D pure copper components by pulsed current plating which could find numerous


applications for both existing and future accelerators. At the end of the year the first large component, a 2.6 m

long RFQ, was successfully plated with 40 microns of copper in the newly completed facilities. Preparations

are now under way to treat a number of other unique large components next year.

Installation Support Group

The Division continued and practically completed its plan for refurbishing and modernizing laboratories in

preparation for handling requests from other divisions (a new laboratory was fitted out in Building 101 and

very deep — 3.20 m — surface treatment tanks installed in Building 102).

The CERN water treatment plant in Building 254 was refurbished.

As it does every year, the group provided divisions in the Accelerator Sector with help needed to meet the

targets of accelerator shutdowns.

The Division was also active in helping set up the facility for assembling and opening LHC prototype

dipoles (Hall Il of the ISR). The large press was assembled and used to open up a 10 m dipole prototype for

examination.

Documents for renewing industrial service contracts were finalized and schedules set to comply with the

official timetable proposed by the Finance Committee.

Informatics Support

In spite of some budget restrictions, the effort started two years ago to upgrade the desktop PCs to a

common standard continued. The local PC servers were migrated to new central machines managed by the CN

Division. The MT users are still locally supported. The program for retrieving and viewing any CERN

drawing was completed with the interfacing of the new microfilming machine. This program always allows

any user to print efficiently and easily the drawings he needs. Apart from the day-to-day support to designers,

the CAD support has almost finished transferring all CERN applications to the Unix environment, in

anticipation of the end of the VMS operating system.

The specific database application called Job Management Toolkit (IMT) is fully operational and interfaced

with the EDH package of AS Division, which allows an integrated and easy follow-up and invoicing of the

numerous MT jobs. The rewriting of the 12-year old application ODD (Oracle Drawing Directory) is almost

finished. This new CERN Drawing Directory application will permit the numbering, approval, archiving and

retrieval of all drawings CERN-wide and will be operational in 1996. A new project was started in order to

give online access to the drawings and their relevant information. First prototypes are very promising.


Proton Synchrotron Division

Operation of the PS Complex, and Accelerator Statistics

The year 1995 was an excellent one for the nine accelerators of the PS complex, with a very high number

of operating hours achieved, and a low fault rate. The machines ran for 6680 hours (not far below the all-time

record of 6800 hours) of which 5600 hours were devoted to physics. Overall availability was of the order of

92% for the different beams to the SPS and LEP, 87% for the beams used by LEAR experiments, and 94% for

the ISOLDE beam. Tables 1-4 show the performance figures for the whole complex, detailed by type of beam.

Table I: Operational statistics for lepton operation in 1995

Total number of hours scheduled for lepton operation 5700

Total number of hours achieved for lepton operation 5258

Hours scheduled for lepton production for SPS/LEP 4538

Hours achieved for lepton production for SPS/LEP 4150

Electrons supplied to SPS/LEP 1.4x 1017 Positrons supplied to SPS/LEP 1.3x 101’

Table 2: Operational statistics for proton operation in 1995

Total number of hours scheduled for proton operation 6630

Hours scheduled for setting-up and MDs 1008

Hours scheduled for proton production (SPS) 4260

Hours achieved for proton production (SPS) 3937

Protons produced for SPS (PSB extraction) 3.57x 10"?

Protons for antiproton production (PSB extraction) 2.49 x 101?

Protons for East Hall test beams (PSB extraction) 3.35 x 1017

Hours scheduled for ISOLDE operation 2511

Hours achieved for ISOLDE operation 2359

Protons supplied by PSB for ISOLDE operation 5.14 x 10?


Table 3: Operational statistics for antiproton operation in 1995

Hours scheduled for AAC operation 5920

Hours achieved for AAC operation 5774

Total number of antiprotons produced by AAC 4.55 x 10"

Maximum stack during 1995 1.04 x 1012 Hours scheduled for LEAR physics operation 4906

Hours achieved for LEAR physics operation 4266

Hours scheduled for LEAR setting up and MDs 1103

Hours used for setting up and machines studies 1024

Total number of antiproton pulses injected 4661

Number of pulses extracted for LEAR physics 4196

Total number of antiprotons injected 2.20 x 1013

Number of antiprotons ready for extraction for physics 1.55 x 10"?

Table 4: Operational statistics for lead-ion operation in 1995

Hours scheduled for ion production (SPS) 1167

Hours achieved for ion production (SPS) 1082

Lead ions for SPS (charges of Pb”>*) 1.28 x 1010

First Operational Period (6 March to 25 June)

After the two and a half month shutdown, dedicated as usual to equipment maintenance and to new

installations or modifications in the machines, the PS complex restarted on 6 March. However, the start-up

period had to be extended by one to two weeks depending on the machine, in order to give time to reinstall and

check the vast amount of Booster and PS equipment which had been removed in a sabotage incident in

February. Thus, during the first month of operation, this work had to go on in parallel with the scheduled tests

of the new slice of the PS control system which had been installed in the shutdown. A great deal of effort was

expended by all the specialists concerned to make sure that every piece of their equipment was working, and

finally, after all this effort and to everybody’s immense relief, the machines worked and the proton and lepton

beams were ready with a delay of only a few days. The only work which could not be completed in time was

the longitudinal recombination of the four Booster beams for antiproton production, which requires long and

delicate adjustments. This beam therefore had to run until August with protons from only two of the four

Booster rings.

The proton beams were adjusted successively: 14 GeV/c beam for SPS, 3.5 GeV/c test beam for AAC,

26 GeV/c production beam for AAC, 24 GeV/c beam for East Hall. By the middle of March good performance

had been obtained with the Booster which was able to extract high-intensity beams reaching 3 x 1013 protons

per cycle to the external dump. Beams exceeding 2 x 10" protons per cycle were accelerated in the PS to

14 GeV/c and extracted for the SPS start-up, and this performance was gradually improved to reach over

2.5 x 1013 protons per PS cycle later in the run, which allowed the SPS to reach a new record of

4x 10% protons per cycle at 450 GeV/c.


After various equipment tests and modulator conditioning, LPI started on 27 March and the first lepton

beam was stored in EPA and sent to the PS a few days later. Lepton beams were delivered as usual to the SPS

in four bunches on the last four cycles of the PS supercycle (twoe* cycles and twoe” cycles with

1.2x 10!! leptons per cycle). However, by the end of May, after tests of double PS fast extraction associated

with RF synchronization had been carried out, it was found possible to use only two PS cycles for the required

lepton beams (2 x 4 bunches per cycle).

The AAC received the 3.5 GeV/c proton test beam during the first week of April, and after a good start-up,

was quickly able to switch to antiprotons. As mentioned above, the production beam was produced by only

two Booster rings (with roughly 10" protons per pulse). Setting-up of the AAC went well and the first

antiproton transfer and deceleration in the PS took place before Easter. Unfortunately, the lithium lens used for

antiproton collection broke down almost immediately and it had to be replaced by a magnetic horn during the

Easter weekend. Following this, and after careful adjustments of the AAC, the stacking rate was increased to

1.9 x 10!° antiprotons per hour with two production cycles per 14.4 s supercycle.

After a period of dedicated machine studies with protons, LEAR received its first antiproton beam on

18 April with good transfer efficiency from the AAC. For several days the antiprotons were used for setting-up

and for further investigations into the causes of the instabilities which had plagued us and the LEAR users for

so long at 200 MeV/c. The result was that these instabilities were effectively eliminated. LEAR physics started

according to the modified schedule with a delay of two weeks with two experiments in parallel at 200 MeV/ec,

CP-Lear (PS195) and Crystal Barrel (PS197). CP-Lear received up to 106 p /s. About 18 LEAR fillings were

achieved in each 24-hour period with an average transfer efficiency from AAC to LEAR of about 75%. Then

LEAR ran at 310 MeV/c and 412.5 MeV/c for OBELIX (PS201) and PS209 in parallel. OBELIX was served

by spills of 40 minutes with 2.8 x 10° p/s. To do that, the AA stack was increased to a high value, even

exceeding 101? antiprotons. Then in June, a new record was obtained at LEAR with a continuous spill of

14 hours at 310 MeV/ec.

ISOLDE started on schedule in April using either high-intensity protons (3 x 10" per Booster cycle) or a

factor 6 less, depending on the type of target. Meanwhile, the East Hall test experiments were regularly served

by 24 GeV/c proton beams from 24 April onwards.

The first operational period ended on 25 June. Over the whole period, very good availability had been

obtained for the proton beams (94.4% for SPS fixed target and 96% for ISOLDE), due especially to the low

fault rates of Linac 2 and the Booster. The global fault rate of lepton beams was 8.3% but a large fraction of

this was not seen by SPS or LEP, when LEP was in collider mode for physics. There was a lower availability

of the antiproton beams for the South Hall users of 87% due to an AA stack loss, a slow recovery after the

eight-hour technical stop on 10 May, and the long stop soon afterwards caused by a general power cut whose

effects were felt for four days.

Second Operational Period (29 June to 15 October)

The second operational run was scheduled for 16 weeks during the summer, one of the longest periods ever

scheduled. The PS delivered the 14 GeV/c proton beam with consistently high intensities throughout the run

(2.2-2.4 x 10" protons per PS cycle) which allowed the SPS to exceed an intensity of 4.2 x 10" protons at

450 GeV/c several times.

"Proton Synchrotron Division

After machine developments and irradiations tests, LPI ran for LEP physics. Double-batch extraction was

adjusted in the PS on 13 July and then kept in this mode (one e* cycle and one e” cycle, both with 2 x 4 lepton

bunches). Later, in collaboration with SPS, the e* and e” cycles were advanced to the 9th and 10th slots of the

PS supercycle. This interesting improvement allowed better flexibility for PS machine developments and gave

the possibility to install three antiproton production cycles in the 14.4 s supercycle.

In parallel, good progress was made on re-establishing the antiproton production beam with four Booster

rings. After reassembling and recabling the beam control modules dismantled during the February sabotage,

long sessions of fine adjustments took place in July. Finally, recombined beams of intensities higher than

1.5 x 1013 protons in five bunches per cycle were accelerated in the PS and were delivered to AAC on

3 August. The average PS intensity was gradually increased to 1.6 x 1013 and even to arecord of 1.9%x 103 in

five bunches, but this value was unfortunately not sustainable owing to the high losses at 1 GeV.

LEAR started this period with one week devoted to cooling and lifetime measurements with lead ions from

Linac 3. Good results were obtained for Pb”** and Pb?* with lifetimes of the order of 10 seconds for strong

electron cooling. Then LEAR worked for physics with antiprotons at 200 MeV/c for CP-Lear (which needed

about 0.8 x 10° p/s) and Crystal Barrel (needing a factor of 100 less intensity). Unfortunately on 21 July, a

vacuum leak on a feedthrough occurred in LEAR which caused an interruption of more than four days for the

South Hall experiments. The Helium Trap experiment (PS205) started on 25 July in parallel with the other

experiments at 200 MeV/c, and every week several fast extractions at 105 MeV/c supplied the experiments

Trap (PS196) and Gravity (PS200). In the middle of September the machine switched to 1940 MeV/c for

Crystal Barrel and Hot Nuclei (PS208) and some 40 hours were also devoted to the Antihydrogen experiment

(PS210) installed in place of JETSET in the LEAR ring. The transfer efficiency from AAC to LEAR was not

stable and quite often went down to 50% or less, needing a constant surveillance by the operating team and

rather frequent readjustments of the machines and beam lines. A good deal of time was spent trying to

diagnose the reason for this loss of transfer efficiency, but no satisfactory explanation was found.

For ISOLDE, the period started on 6 July with high intensities, often just exceeding 3 x 10" protons per

Booster cycle. Unfortunately the ISOLDE target broke on 17 July and ISOLDE experiments had to be

suspended until the beginning of August. Then after three further weeks with high intensity, a new mode of

Booster extraction was tried for one of the ISOLDE molten metal targets: three Booster rings were used, and

their extractions were staggered in time from a few us up to I ms. This test proved successful and may

possibly develop into an interesting mode of operation for ISOLDE, but for the moment it cannot be

considered operational. ISOLDE experimenters finished the period using the high-intensity beam but were

disturbed by a Linac 2 breakdown in October.

The East Hall experiments started on 17 July with the usual average intensity of 3 x 10! protons per PS

cycle, shared among the four test lines. The only problem was for the T7 line where a water leak in a bending

magnet could not be repaired until the October shutdown.

Over the whole period from 29 June to 15 October, the availability of the beams was 91% for both protons

and leptons, but only 86.4% for antiprotons. This lower performance level was partly due to major problems

with the LEAR vacuum in July and to several faults affecting AAC, PS and LEAR (high-voltage transformer

breakdown, power supply of the magnetic horn, LEAR 18 kV station, LEAR power supplies).


Third Operational Period (19 October to 20 December)

The third operational period proved to be the best one of the whole year from the point of view of the

operational performance of the PS machines, with an availability for physics of 94.65% for lead ions, 91.7%

for leptons, 88.1% for LEAR experiments and 95.9% for ISOLDE.

After a short, three-day shutdown for equipment maintenance, the PS complex restarted on 19 October for

the third operational period. After the machine setting-up with protons, the SPS switched to lead ions which

were delivered on the first four cycles of the 19.2 s supercycle in the PS. Beams of 1.1 x 101° charges of Pb>*

were routinely accelerated in the PS and about 1.7 x 101° charges of Pb$** resulted from the stripper device

installed in the TT2 line. After the setting-up of the SPS machine, the lead-ion beam was used in November by

the fixed-target physics programme.

Meanwhile, ISOLDE worked with further tests of the staggered extraction of three Booster rings for a total

intensity of 103 protons per cycle. By the end of November, ISOLDE switched back to the normal fast

extraction with four Booster rings and high intensity (3 x 1013 protons per cycle, and 7 or 8 cycles per 19.2 s

supercycle). During this time, the East Hall used one or two cycles whenever AAC was not requesting the

production beam.

Lepton operation for SPS and LEP continued to run well until LEP stopped on 27 November. There then

followed irradiation tests in the LIL experimental area (LEA) and machine studies on LPI.

LEAR started this last operational run at low momentum (105 MeV/c) with OBELIX (PS201) and

Ionization (PS194) sharing the antiproton beam (10° p/s each). Then Crystal Barrel (PS197) replaced PS194.

There were quite a few problems in November affecting the antiproton beam for the South Hall experiments,

with the result that the availability for physics did not improve much over its rather low value of the previous

runs: AA and AC both had RF problems, a water leak developed on AAC, the PS magnetic field developed an

instability, there was a LEAR air-conditioning fault, a replacement of the magnetic horn was required, and

there were three general power glitches. In addition, OBELIX (PS201) suffered from an abnormally short spill

caused by a poor antiproton lifetime in LEAR at the lowest momentum of 105 MeV/c which may have been

the result of contamination by xenon gas remaining in the machine after the run of PS210 in the JETSET

position. However, the LEAR run continued successfully until 13 December for PS207 at 105 MeV/c, with

good transfer efficiencies reaching up to 85%.

After the physics stopped, there were machine development sessions on the PS (tests of the strippers for

Pb°** ion production in conjunction with the SPS), on the Booster (studies with lead ions and protons), and at

LEAR (electron cooling tests with lead ions, and beam lifetime measurements for Pb’>*, Pb°**, and Pb”*

ions to confirm the June results). Finally, in the week before Christmas, tests were made for the second slice of

the renovated PS control system which concerned all aspects of proton and positron extraction from the PS.


Leptons

Throughout 1995 the LEP pre-injector (LPT) supplied lepton beams for LEP with an availability of more

than 95%, including the stops caused by power failures, which is a very satisfactory performance level.

During the shutdown at the beginning of the year, a section of the linac used for positron trapping, together

with its focusing lenses, was exchanged with the spare unit in order to replace radiation-damaged solenoids

and to improve the accelerating section so that it could sustain higher RF fields. This enabled experiments to

start on a more efficient use of modulators, by employing the higher trapping fields produced by a power pulse

compressor. In addition, by replacing the modulator used to power the bunching system of the linac, which

runs at low power level, and by a diverting some fraction of the power from another modulator, it was possible

to produce the normal lepton beams using only five modulators instead of six, with consequent savings on

maintenance of these complicated devices. The technical consequences of running permanently in this way are

being evaluated with a view to implementing such a scheme for the 1996 start-up.

Protons

Linac 2 and Booster

Studies made on the RFQ test stand at the end of 1994 had indicated that a purely mechanical alignment of

the source, Low-Energy Beam Transport (LEBT), and RFQ was inadequate and that an alignment using the

beam itself was necessary. So, during the 1995 shutdown this exercise was tried on the pre-injector installed

on Linac 2. The source, LEBT and RFO in front of the linac were first re-aligned mechanically, and then

further adjustments were made using the beam arriving in the linac. First tests quickly demonstrated the value

of this exercise in that the beam transmission in the first linac cavity improved and an overall gain in intensity

resulted.

Linac 2 first provided beam to the PSB back in 1978, and since then very few problems have arisen in the

linac structures. This year proved to be an exception, however. In early October a major leak, which proved

surprisingly difficult to locate, developed between tanks 1 and 2 of the linac. The leak, whose repair would

have involved an extended shutdown, was bypassed by applying a rough vacuum around the fault and this

temporary solution proved adequate until the next machine stop when it was reinforced to enable the linac to

continue running until the end of the year. The diagnosis and repair of the leak is a high-priority job for

the 1996 annual shutdown. Apart from this incident, Linac 2 continued to operate in its usual efficient and

reliable manner.

On the Booster, a very necessary vacuum job was tackled in the long shutdown, the replacement of all the

corroded bellows on the septum tanks. At the same time, their position acquisition electronics was renewed

and the replacement of kicker high-voltage cables was completed, having been started in the shutdown a year

earlier. Acceleration of protons, in particular the critical high-intensity beams for neutrino physics and

ISOLDE experiments was carefully tuned, including reprogramming of the dynamic working points of the

four rings. When comparing statistics one finds that 1995 intensities are more than 15% higher over most of

the year than in 1994.


On what would otherwise be spare machine cycles (usually about six per supercycle), the PSB delivers

proton beams to ISOLDE. Frequently this requires maximum intensity on these cycles, which is critical as the

tolerance for beam loss becomes tighter and tighter. A modification of the optics in the transfer line was

successful in reducing the losses at the end near the ISOLDE target. Tests of a new mode of operation were

made in August, the so-called ‘staggered-beam’ mode, featuring the introduction of a delay of 10 us between

the sequential extraction of individual Booster rings. The result was a spectacular rise in the intensity that

molten metal ISOLDE targets could withstand, paving the way for improved yields of exotic isotopes. This

technique was subsequently tested with a variety of target elements and may one day become an important

mode for ISOLDE operation. Another milestone for ISOLDE was the first operation in December of the High-

Resolution Spectrometer (HRS) branch which received beam for the first time for physics.

PS and Transfer Lines

During the long shutdown, a survey check of the positions of all 100 PS magnets was undertaken in order

to update the magnet position database, as was done for the TT2 transfer line in the previous shutdown.

In the course of the year, one of the two PS internal dumps broke down and had be removed. No spare unit

in working order was immediately available, but work started on preparing a unit for installation in the next

shutdown. In the mean time the PS had to run with only one internal dump target. These target units are

important because they are used if it is necessary to kill a beam in a controlled way inside the PS for any

reason.

The spare unit of the staircase generator was brought into operation to drive dipole DFA243 in the

TT2 channel and thus to allow a better control of the position of the two last turns of the extracted beam in the

continuous transfer scheme. This reduced the overall emittance of the high-intensity proton beam transferred

to the SPS and improved the transmission.

Automatic Beam Steering (ABS), already available to correct coherent oscillations of the proton beam at

injection, was implemented for the injection of positrons into the PS.

A water leak developed on a coil of SMH57, one of the septum magnets used for slow extraction to the

East Area, and the magnet was replaced during the short stop in June.

Consolidation Work

The work on refurbishing the Booster septa positioning mechanisms, their cabling and controls, launched a

few years ago as part of the consolidation programme of the PS complex, was completed during the long

shutdown. Also as part of this programme, solid-state triggers were installed for the EPA kicker pulsers.

Another major development was the renovation of the electronics of the PS main generator. Together with the

control and measurement of dB/dt, this new equipment allows a more precise and temperature-independent

regulation of the magnetic field in the PS main magnet.

For the Booster, the renovation of the main power supply is now under way. This has been under

discussion for a long time, both because of the presence of old equipment containing PCB, and because of the


desire to reach a higher energy for the Booster. The specifications are being prepared in collaborations with ST

Division and with TRIUMEF, Canada.

As part of the modernization of the huge number of power supplies around the PS, 1995 saw the upgrading

of a number of power converters and their electronics: 16 units for the injection quadrupoles of the PSB; 5 for

septum bumper 42 (SMH16, SMHS58, SMH74, SMH92, SMHO00); 10 of the type R2B for the transfer line

magnets TT70 and the magnets in the East Area.

Antiprotons

The performance of the AA and AC machines in 1995 was the best ever obtained, with an availability of

97.5% for a total of 5920 hours of operation, during which 4.56 X 10" antiprotons were produced altogether,

of which 3.62 x 1013 were delivered to LEAR. However, in spite of this success, the month of November was

a black one, with a series of breakdowns (a water leak, several power cuts, radiofrequency problems) which

resulted in five separate stack losses and caused serious disturbances to some of the LEAR experiments.

In the target area there were two incidents which caused concern. During the start-up in April, the lithium

lens which had been so reliable for over three years broke down. A short circuit developed in its primary

transformer winding, and so it had to be replaced. This was the last such unit, and it had already been decided

that when it finally broke it would be replaced by a magnetic horn; such a horn collects about 15% less

antiprotons but is a more robust device, and the loss of antiprotons could be compensated by running the

production for a longer time. The antiproton production rate needed is about 1.7 x 1010 per hour. In September

there was another incident when a broken fixing bolt was discovered on the horn unit. As a precaution the horn

was replaced but unfortunately this too had to be replaced after only three weeks when it was burnt out by an

accidental overvoltage from its pulser.

The machine development sessions on AAC were mainly done this year in the shadow of normal running,

and were aimed at maintaining the performance level of the machines. The stochastic cooling of bunched

beams and the deceleration of beams in AC were studied while running in economy mode and encouraging

results were obtained; a proton beam was decelerated from 3.5 GeV/c to 1.7 GeV/c, all that was possible with

a minor modification to the existing RF system.

The LEAR programme for 1995 consisted of a three-week development session at the beginning, followed

by long physics runs interspersed with a few short study sessions. During the physics runs, two or even three

experiments took beam simultaneously, and the trap experiments were given fills using fast extraction for

short periods whenever possible. Very different modes were needed for LEAR during these physics runs:

ultra-slow extraction lasting from 1 to 14 hours with fluxes of 10* to more than 2 x 10° p/s; fast extraction at

105 MeVf/c to satisfy the trap experiments; and a circulating beam of 2 x 1010

by experiment PS210 for the fabrication of nine identified antihydrogen atoms.

antiprotons at 1.94 GeV/c used

Electron cooling was used in LEAR to supplement stochastic cooling whenever the physics needed a beam

of less than 310 MeV/c, thus reducing the time between spills. Some lengthy study sessions were devoted to

understanding the neutralization and instabilities of the electron beam but good progress was made, in

collaboration with colleagues from Dubna.


The antiproton beam instability, or so-called “‘phantom’ in LEAR which for two years caused sudden and

unexplained beam loss at 200 MeV/c (and only at this momentum), was eliminated by installing additional

cleaning electrodes to remove pockets of ions or charged dust particles, but above all by installing a feedback

system derived from the beam signal. As a consequence, the 200 MeV/c spills with 10° p/s were much more

stable and regular, and for the experiments needing a low flux, spill times of, for example, 10 hours (see

Fig. 1) and even up to 14 hours were produced. This greatly improved beam quality was one of the highlights

of the year at LEAR.

40000 F” p/s ||

30000 F

20000 \ PS209 experiment

10000 F

aoooo F p/s |

30000 | -

20000 | I OBELIX experiment

10000 |

0 2 4 6 8 ’0

Fig. I: Measurement of the remarkably steady flux (- 3x1 0° 9/5) received by

the two LEAR experiments at 310 MeVV/c over a IO-hour period, only interrupted

by the entry ofthe OBELIX physicists into their area.

Ions

In Linac 3, the shutdown and the early part of 1995 were used to consolidate the machine after its first

operational run at the end of 1994. The major jobs involved modification of the inter-tank quadrupole triplets

to make them mechanically more flexible and the installation of the first definitive 100 MHz amplifier chain

on tank 1; two amplifier chains on loan from GSI had been used in 1994 and one of these remained for use

in 1995. These amplifiers had been designed by industry under the supervision of GSI as a contribution to the

Lead Ion Accelerating Facility, but were unfortunately subject to many teething troubles. However, they did

prove reliable for the 1995 physics exercise.


The opportunity was taken during these modifications to carry out some investigations on the source. In

particular, a new extraction geometry was found giving a higher extracted ion yield which was used for the

remainder of 1995, but tests on the ECR ion source gas mixture, where the addition of neon to the normal

oxygen was predicted to give increased yields of the desired lead ions, proved inconclusive.

From the operational point of view, Linac 3 was available from the beginning of summer providing test

beams not only for LEAR but also to the PS and PSB, in anticipation of the 1995 ion physics run at the end of

the year. During this run the increase in intensity obtained from the source was maintained through to the

output of Linac 3, and efforts were made to bring the operational reliability of this linac to the same level as

Linac 2. Beams of more than 25 uA of Pb>’* were supplied to the downstream accelerators and the physics

run was a great success. The end of the year saw LEAR again taking beam, during which the linac was

required to provide not only Pb°>* but also Pb”*, Pb?** and Pb°°* which it proved capable of doing at short

notice. Unfortunately, the reliability of Linac 3 during the last week of operation was not very good.

The sabotage incident of February had some consequences for the Booster, especially for the critical RF

captures which had to be readjusted from scratch and homogenized for all four rings, but injection steering

was much easier to control following the installation of new, highly sensitive scintillator screens and modern

CCD cameras in the injection line. Thanks to the increased current from Linac 3 and the improved injection

line, the intensity injected into the Booster was well above the 1994 mark. Thus, an average of

1.58 x 10!° charges of Pb°>*+ per cycle was accelerated in the Booster during run 3, roughly 25% more than

last year. The record was as much as 2.2 x 101° charges. This performance would have been even better if

there had not been a new vacuum leak in ring 3 strongly affecting the lifetime of the ions. After acceleration in

the PS and extraction towards the SPS, further tests were needed to find the best stripper foil thickness, and it

was found that 0.8 mm of aluminium foil gave the optimum transmission.

Lead ions had been delivered to the users for a first physics run in November 1994, but although the

facility was up and running at that time, a number of elements needed further attention, either because our

brief operating experience showed that improvements were necessary (e.g. vacuum equipment, especially for

the Booster, mechanical alignment of the intertanks of the IH-Linac, instrumentation in the stripper line, etc.),

or because the element in question had still to be definitively installed (e.g. the 100 MHz power amplıfiers). In

addition, all sorts of spare parts had to be ordered (e.g. a spare 100 MHz RF amplifier, spare drift tubes and

triplets for the IH-Linac, spare pumps, etc.). These jobs were done throughout 1995, prior to the ion run

foreseen for period 3. The quality of this second physics run clearly showed the benefit of all this

consolidation work; there were intensity improvements at every stage, with the design figures exceeded from

the source right through to the experiments. This is a remarkable achievement, and is a tribute to the quality of

the equipment made by the collaborating laboratories, as well as to the fact that during the construction, a very

close working relationship was established between the outside experts and their CERN counterparts with a

view to ensuring that what was delivered could be integrated into the existing PS environment and be readily

exploited by PS operating staff. This was the first time that a major new facility at CERN had been constructed

with so much outside participation, and it has been a successful experiment.


Experimental Areas

LEAR Experimental Area in the South Hall

Eleven experiments took data over the 30 weeks of LEAR operation in 1995, and in 25 of these weeks

either two or three experiments ran simultaneously using splitter magnets. The slow extraction mode was used

most (85%) of the time at beam momenta ranging from 105 to 1940 MeV/c. Fast extraction was set up for

PS196 and PS200 (Trap experiments) at 105 MeV/c and PS205 (Helium Trap) at 200 MeV/c. Several new or

improved optics solutions were commissioned, in particular for PS209 (Neutron Halo), PS205 (Helium Trap),

and PS185 (Spin Transfer); and to fulfil the beam requirements of experiment EMU2O a special titanıum

vacuum window of 90 mm diameter and 0.025 mm thickness was installed and the optics verified.

Experimental Test Area in the East Hall

The East Hall ran for 25 weeks altogether, providing test beams to 40 different groups of physicists.

However, following a water leak in magnet FT61.BHZ03, one of the four beam lines (the south branch, T7)

was unfortunately out of operation for two weeks. With a view to delivering test beams for the detectors of the

future LHC experiments (ALICE, ATLAS, CMS, LHC-B), as well as to satisfying the request of the

forthcoming DIRAC experiment, beam calculations were carried out to replace the present beam lines in the

East Hall by new ones making use of the whole of the hall. Beam optics studies have also been performed in

preparation for a low-energy, fast extracted proton beam to PS211 next year as a follow-up to the Energy

Amplifier Test made in 1994, and for a slow extracted beam to be shared between several users.

At the request of the users, an interesting machine development session was devoted to the delivery of a

3.5 GeV positron beam to the East Hall in fast extraction mode. This was successfully achieved up to the first

TV monitor of the primary beam line and opens the possibility of providing pure primary (and not secondary

as at present) positron beams to the users of this area at some future date.

ISOLDE Area

The 60 kV pulser for the target station of the ISOLDE High-Resolution Separator (HRS) was installed and

put into operation.

LEA (Experimental Area at LIL) and EPA Test Area

There have been regular irradiation sessions during 1995 in the LIL Experimental Area (LEA) for several

different users from the OPAL and ECAL/CMS collaborations to study detector component performance,

profiting from better beam tuning due to improved instrumentation in this area, and new alignment hardware

for the experimental equipment. Irradiations were also made at the Electron Positron Accumulator (EPA) ring

during periods when LEP did not need it. The EPA operates normally at 500 MeV, but if it is run at 308 MeV,

it produces synchrotron light which simulates what will be generated in the LHC by the proton beam. The

LHC vacuum group initiated this work, whose aim is to study gas desorption at cryogenic temperatures

induced by synchrotron radiation, in order to predict the vacuum behaviour of the LHC machine. Data taking

will continue next year on this important subject.


Computer Controls

Controls activities in 1995 were dominated by the PS controls consolidation project D-067. The slice

concerning PS injection was installed in the long shutdown and for the rest of the year preparations were made

for the next slice (PS extraction and transfer lines).

The strict daily follow-up of controls problems by the exploitation team has resulted in very good

reliability which meant that there was enough time for the experts to work on the controls consolidation

project. The exploitation of the new controls installed over the last few years (at LPI, the linacs and the

Booster) has demonstrated the very high quality of the ‘CERN standard controls architecture’ which has a low

fault rate, thus minimizing the need for interventions by experts. Furthermore, the improvement of the

diagnostics and exploitation tools has provided a very efficient way for the exploitation team to run the system.

Nevertheless, it is a major effort by the on-call controls team to keep the PS accelerator complex in good

working order.

The first quarter of the year was used for the usual preventive maintenance of the running computers and

the interface hardware, and to start up the new controls for PS injection. After a very short running-in period,

the system was stable and efficient. The usefulness of the Pulse-to-Pulse Modulation (PPM) architecture of the

equipment manager (the Equipment Module), complemented by the new reference value and archive database

services, was amply demonstrated throughout the year. The low-cost, function generators GFAS (geEnerateurs

de fonction analogique simple) were a major development, making it possible to modulate one function by

another one, in order to give dynamic modulation without a complete redefinition of the function vectors. The

power of this new device for the RF controls is that it brings a dramatic reduction in the amount of hardware

needed to perform all the necessary RF gymnastics demanded by the various beams of the PS machine. The

high performance version GFAD (gEn£rateurs de fonction digitale) were equally well appreciated in providing

the necessary flexibility in controlling magnets and RF devices.

During the year the management of the front-end computers, the Device Stub Controllers (DSCs), was

completed with a configuration-independent suite of procedures for connection to process interrupts. The

bindings between hardware interrupt sources and the logical sources for the software client are done by the

configuration manager, from data that describe the VME chassis in Oracle. This facility completes the

manager functionality and provides a smooth way for the basic hardware and software components of aDSC

to evolve without disturbing the various specific software packages.

A direct result of using modern hardware and advanced software technology is the possibility of data-

taking every millisecond for many beam diagnostics devices. This provides the application programs with

much more potential for displaying information efficiently and in more user-friendly ways. Online diagnostics

was also improved by new versions of the SETUP and BCD checker facilities: SETUP is a software package

based on an expert system designed to retrieve normal conditions in the hardware interface after a stop, and

was developed in collaboration with PNPI, Gatchina, Russia; the BCD checker is a coherence analysis tool for

the state of the beam sequencer of the PS complex (the Program Line Sequencer or PLS system) and it too

uses expert system technology which is a direct spin-off of the E.U. Esprit project ARCHON. Other new

software was the exploitation tools suite called BRED (Browser and Read-only Editor) which provides a way

to do quick fixes and updates of the read-only data in the equipment data tables. This facility was provided in

collaboration with IHEP, Protvino, Russia and was a big help to the exploitation team during the start-up after

the long shutdown.


Preparations for the migration to the new RS-6000 platform architecture for our workstations and file

servers was a major task needing a very systematic review of all the sources of the control software packages

and facilities. This was coupled with a complete reorganization of the file system structure which allows a

better control of the development and production cycle of software. The decision to use the AFS file system

provided and supported by CN Division gives us a better and more uniform view of the software sources from

the various platforms available at CERN, and the daily and long-term backup should be much easier since it

will be done automatically by CN. The order for the file servers and the online workstations was sent out in

autumn, and the first batch of 63 computers arrived in December for installation during the shutdown.

The strategy employed to implement the latest controls conversion slice, as in all the previous slices, was

to re-use to a maximum the developments already implemented in those slices and to add new facilities to

match any new needs. This strategy again proved very successful because, even with a reduced team, it was

possible during the last week of the year to switch the PS controls from the old Norsk Data system to the new

architecture in only two days, and to run the PS to produce a proton beam immediately. This success gives

full confidence that the new architecture can run fast-ramped machines like the PS with very demanding

timing, and in PPM mode. During these tests, a new kick strength unit (KSU) driving the full aperture kicker

KFA 71/79 was also successfully commissioned.

Decoupled from daily controls tasks, a small team working on object-oriented software technology

produced an object-oriented version of the workstation equipment access package, and a first prototype

program using CDEV technology from CEBAF in the context of the EPICS collaboration, which was very

much appreciated in the world-wide software sharing working group (SOSH). These results give confidence

that this technology will be useful to us in the future.

Office Computing

The office computing network which has allowed such effective communications in PS Division over the

past few years is being modernized by the gradual installation of new structured cabling by CN Division in

those buildings where this is possible. The old “ethernet’ serial cable link is being replaced by cables to

individual users from a number of star points, with the object of improving the stability of the whole

computing environment.

Consistent with the CERN policy of centralizing the office automation services, the remaining Novell

Netware 3 servers in PS Division were closed down and the services migrated to CN Division. However, a

very close collaboration with CN remains essential in order to ensure that any evolution of the NICE

environment corresponds closely to the needs and desires of the users. To this end, our Division is

participating actively in the development and evolution of the future operating system Windows95, which is

due to become operational in 1996.

The policy with regard to the Division’s inventory of PCs and Macs is that for new machines, only the

highest performance units are purchased, whereas the older, lower performance units are upgraded wherever

possible by adding memory capacity or by increasing the CPU speed. This ongoing policy aims at maintaining

an homogeneous inventory of office computers, so as to keep the support and maintenance to a minimum. For

the same reason, we rely on NICE for practically all our software, to reduce its diversity where possible.


The gateway or “passerelle’ which permits a strictly controlled and limited access from the PC platform to

the PS control system has been completely renovated. The performance has improved and a Program Line

Sequencer (PLS) synchronization mechanism has been added. This means that any MS-Windows application

written in C, Visual Basic, Excel or even Word can be synchronized with the telegram of the PS accelerators.

Using these standard commercial tools, a set of diagnostics and documentation applications has been

developed for the PS-CO exploitation section with great success.

In the Main Control Room (MCR) the tasks performed by some PCs, for example the log-book function,

require a reliability better than can be guaranteed by the central services in CN Division. For this reason, a

Novell server integrated in the NICE structure will be physically installed in the PS and directly connected to

the MCR PCs in the course of 1996 so that any public service or NICE server fault will no longer affect the

functioning of the MCR.

Beam Diagnostics

Keeping the Division’s 1500 beam measuring devices in good shape was a major activity during 1995. It is

worth noting that software maintenance has now become a load comparable to that of hardware maintenance,

a fact that underlines the importance of standardization also in the software for beam diagnostics. The

appointment of a systems integration coordinator two years ago clearly had a beneficial effect in this respect.

The continuing conversion of the PS control system once again implied widespread changes to the specific

controls of the diagnostic systems, often with repercussions on the electronic hardware. On the PS, the closed-

orbit measurement system, comprising 40 pickups measuring the beam’s horizontal and vertical position, was

converted to the VME standard, in line with the PS controls conversion. The old and the new system were run

in parallel in December to prove that the new system will work correctly for the start-up in 1996. The d.c.

beam transformer of the PS was also converted to the new controls standard, and in so doing its operational

facilities were enlarged so that, apart from just the intensity, the complete waveform can now be acquired for

detailed analysis. At the same time, in the various transfer lines around the PS, beam transformers and pickups

which used an outdated computer to run their specific controls were treated to a profound clean-up action by

installing modern, standard controls.

At the lead-ion Linac 3, consolidation work was done on two types of phase probes, while for Linac 2 the

installation of a three-dimensional bunch shape detector was prepared in collaboration with INR, Moscow.

Beam transformers in the line from the linacs to the Booster necessitated careful studies to counter the noise

perturbations which had been observed recently. Very important work continued on the Booster transverse

damper, especially on the digital delay control (necessitated by the Booster’s large frequency swing), and on

the BOSS (Beam Offset Signal Suppressor) which will reduce the noise and the power required, as well as

enhance the dynamic range. But the biggest single item tackled was the complete renovation of the pickup

system in the recombination and transfer line from the Booster to the PS. Here, the acquisition electronics and

the specific controls were replaced completely by the best modern equipment, to guarantee precise beam

position measurements even under the unfriendly conditions prevailing in this region. All this is part of the

preparations of the PS complex as LHC injector.


An interesting new development took place in the beam line used for the ISOLDE group. After promising

tests in 1994 with a SEM-grid at the ISOLDE target position, a new heat-resistant type was developed for

permanent installation in front of the targets for both the GPS and HRS separators. The same type of SEM-

grid will find application also at the new PS injection septum 42.

Although no further upgrades were carried out around LEAR, a novel ‘smart’ digital filter for its d.c. beam

transformer was tested with beam. It greatly improves resolution and renders the transformer less sensitive to

the perturbations which are abundant in that region.

Support was also given to CTF by constantly adapting their diagnostic devices to the changing needs of

this experimental facility, and assisting in tests of a new streak camera with a resolution of 3 ps, twice as good

as the one currently in use. In the context of LHC preparations, considerable effort was expended in the study

of divers beam diagnostic equipment for the future LHC machine, in collaboration with SL Division.

Preparations of the PS Complex for the LHC

Studies of Lead Ions in LEAR

The use of LEAR as a low-energy ion accumulator ring with electron cooling is foreseen in the LHC

conceptual design study. The series of tests with lead ions from Linac 3 injected and cooled in LEAR in order

to confirm this scheme have continued with two sessions in June and December 1995. The first measurements

using a Pb°>* ion beam in December 1994 had shown that the lifetime of the beam in the presence of electron

cooling is very short, supposedly due to the recombination of the ions with the electrons of the cooling beam.

This short beam lifetime was considered a serious difficulty.

The machine development session in June was devoted to comparative lifetime measurements of

neighbouring charge states (Pb?2*, Pb°3+, Pb°**) which can be obtained with almost equal intensity from

Linac 3. This experiment clearly indicated that Pb°2* and Pb°** are much less sensitive to recombination

losses than Pb”’* ions. The 1/e lifetime at 400 mA electron current is 8 or 9 seconds compared to 2 seconds

for Pb°>*. This result was published in Physics Letters B and has intrigued atomic physicists and cooling

experts, but as a consequence of the test the project will now be based on the storage of Pb°** which has a

sufficient lifetime to allow accumulation and storage during the time of aPS cycle.

In December the development time was devoted to exploring the transfer line from Linac 3 to LEAR, and

to studying the influence of the LEAR lattice functions on the cooling speed. By improving the matching of

the injection line, up to 2x 10° charges could be injected in a single-turn mode. Results concerning cooling

seem to indicate that the optics of the machine does not have the strong influence on cooling time that it should

have, a result which is not yet understood. Effort was devoted to the study of the cooling as a function of the

betatron amplitudes, neutralization state, lattice parameters, and the influence of the residual gas composition.

More time is needed for the detailed evaluation of these results, and further dedicated time will be needed next

year, even though this is the last year of LEAR operation and the experiments will want as much beam as they

can get. During the same December session the longer lifetime of Pb>** and Pb°** ions compared to Pb>>*

was re-confirmed and a decay rate of Pb°>* similar to that of Pb?2* was found.


LHC Preparations in the PS

Following a successful beam test in late 1993, which demonstrated that the PS could indeed produce a

proton beam of sufficient brightness for the LHC, the project to prepare the PS for the LHC era is now well

under way.

The prototype 40 MHz RF system for the PS, which will generate the 25 ns bunch spacing for LHC, is

nearing completion: fine machining of the cavity is finished and the whole assembly has proven leak tight in

an oven; the mechanical short-circuit has been built and tested for a few thousand movements under vacuum;

the 300 kW amplifier chain is now assembled. After delivery of all the components, high-power tests of the

complete system, including HOM (high-order-mode) dampers and tuning and voltage servos, are planned

for 1996 in a zone specially equipped for this purpose. Machine experiments with beam in the prototype

cavity will become feasible after its installation in the PS in late 1996.

Another major development dealt with a new pulsed PS injection septum magnet SMHA2 as well as its

(capacitance discharge) power converter supplying 33 kA. After thorough tests in the laboratory, both will be

ready for installation in the 1996 shutdown. This bakeable septum will enable the injection of 1.4 GeV protons

into the PS, and will serve as a prototype for the new PSB extraction and recombination kickers and septa.

Gas-filled transmission cables for the extraction kickers have been installed and development work on the

prototype pulse generator is in progress.

Two wideband transverse beam position monitors are being assembled and tested; they aim at observing

the individual bunch position of short (4 ns) LHC-type bunches in the PS-SPS line and thus to check the

quality of PS extraction.

On top of these hardware milestones, most people involved in the project worked on the definition,

specification and prototyping of equipment to be provided at a later stage, in particular magnets and power

converters of the PSB-PS line, fast kicker magnets, the PSB main magnet power supply, the new h=1 RF

cavities of the PSB, and beam diagnostic devices.

Two machine physics results are worth noting: the PS-SPS transfer line can accept a momentum bite of

+0.4% which is more than anticipated and provides welcome flexibility in matching the beam to the SPS

needs; single bunches can be generated in the PS with characteristics similar to those of the future LHC beam,

thus enabling the SPS to find out about longitudinal microwave instabilities which may severely limit its

performance for LHC.


CERN Linear Collider Studies

Compact LInear Collider (CLIC ) Theoretical and Technological Studies

The single-bunch parameters for both the 500 GeV and 1 TeV centre-of-mass machines were updated at

the beginning of the year to obtain an optimum luminosity for an acceptable beamstrahlung parameter (< 5%)

and acceptable experimental background conditions. A revised CLIC parameter list was issued to meet the

luminosity and energy requirements of 5 x 10° at 500 GeV and 10° at 1 TeV set by the International Linear

Collider Collaboration Committee for a future world machine. In particular the new list assumes 10-bunch

operation, and as a consequence more effort has been devoted this year to studying the production of long RF

power pulses and the associated long drive-beam trains.

Computer optimizations of the variable-charge drive-beam bunchlet trains for the 1 TeV multibunch

machine have shown that the maximum tolerable main linac bunch-to-bunch energy spread of +0.2% can

be met. A drive beam generation scheme for a 15-bunch mode of operation at 1 TeV has been devised, based

on 18.5 GV of 352 MHz LEP2-type superconducting cavities and 2 GV of 1400 MHz superconducting

cavities, distributed in four separate linacs to accelerate the beam to 3 GeV. An alternative, more efficient drive

beam scheme using an isochronous ring is also being investigated. This scheme uses continuous bunch trains

to supply power sequentially to small sections of the main linac.

The main part of the beam dynamics work has in the past been devoted to single-bunch emittance

preservation studies. For the multibunch mode of operation new investigations have been launched to test

analytical and numerical methods of controlling the total emittance; these include BNS (Balakin-

Novokhatsky-Smirnov) damping applied to multibunches (in collaboration with the University of Madeira),

calculations of acceptable wakefield attenuation levels, and simulations with double the number of

quadrupoles. A possible design for an isochronous three-bend achromat has been developed and proposed as a

module to be used in the 360° bends and possible rings that are needed in the injection schemes for the main

and drive beams. Tracking programs have been developed for the intense multibunch drive beam to study the

control of beam break-up through strong variable focusing, to deal simultaneously with space charge forces,

wakefields and propagation effects, and to estimate losses associated with transverse deflecting fields (in

collaboration with CEBAF). Particularly powerful correction methods based on dispersion and wakefield-

effect direct measurements have proved very effective in reducing the vertical emittance.

Design studies of main linac accelerating structures for multibunch operation are continuing. A damped

cavity solution with two or three output waveguides in each cell is being investigated. The development of RF

quadrupole sections has progressed. These are needed to compensate single-bunch wakefield effects. More

than 50 have been obtained from industry, demonstrating that the machining of these non-circular cells to the

required micron tolerances and mirror surface finishes is indeed possible. Multibunch operation complicates

the interaction region of CLIC since it excludes the straight-through on-axis collisions. Studies of interaction

regions with small (0.5 mrad) crossing angles have shown that strong beam-beam kicks creating a ‘kink

instability’ with a severe loss of Juminosity make this solution impractical for more than two bunches.

The collaboration between CERN and the Centre d’Etudes Scientifiques d’Aquitaine (CESTA) in

Bordeaux to study an alternative scheme of drive-beam generation by direct bunching at 30 GHz in an


induction linac driven FEL has continued on the 2 MeV 1 kA LELIA machine and has resulted in a ‘world-

first’ direct observation of beam bunching by an FEL. New collaborations between the CLIC study group and

CEBAF and LBL have also been created this year.

CLIC Test Facility (CTF)

One of the main activities in 1995 was the running and exploitation of the CLIC Test Facility (CTF) with

the newly installed magnetic bunch compressor and the 4.5 m long LIL accelerating section replaced by al m

long high-gradient section on loan from LAL/Orsay. The new layout enables a 1.5 m long section of beam line

to be used for testing components. During the course of the year a very rich and rewarding experimental

programme was carried out, as follows:

— The bunch compressor was used to reduce the length of single bunches by a factor of 2 to 4 (depending

on the charge) to a minimum measured of 3 ps FWHH.

— A two-channel CLIC Transfer Structure (CTS) was tested with beam, revealing unacceptable field

inhomogeneity problems. A new four-channel transfer structure with a highly improved field

homogeneity has been designed specifically for CTF2 and has proved successful both in tracking

calculations and with beam in the CTF.

- Two large-aperture button-type broadband Beam Position Monitors (BPMs) for the drive beam with

their associated signal-processing systems were tested.

— The 30 GHz small-aperture narrow-band BPM system foreseen for the main linac was tested. The set-

up consisted of two resonant cavity BPMs and a charge normalization/phase reference cavity. A

five-channel super-heterodyne receiver was used in the signal processing electronics to obtain charge-

independent horizontal and vertical positions in each BPM. Both BPMs were mounted on 0.1 um

resolution micro-movers for displacement calibration. An upper limit on resolution of #4 um was

demonstrated. The measurement was limited by the shot-to-shot angular jitter of the CTF beam.

—- A wall current monitor was used to measure the bunch charges in a bunch train.

— Bunch length measurements were made at the outlet of the spectrometer using a coherent radiation

monitor built by the TESLA team.

— 60 MW 30 GHz power pulses (10-20 ns long) generated by passing a 24- or 48-bunch train through a

prototype high impedance CLIC main linac accelerating structure were used to test a power limiter, a

1O cm section of flexible WR28 waveguide, a stainless-steel waveguide load, a ceramic waveguide

load, a WR28 phase shifter, and a high gradient waveguide test section. No evidence of RF breakdown

was observed in any of these tests.

— A GaAs cathode prepared by SLAC was put into the RF gun and operated up to 85 MV/m. This is an

important step in the study of the production of polarized electrons for future linear colliders using an

RF gun. Collaboration with SLAC on this subject will be pursued.

CTF in its present configuration (CTF1) has achieved all its objectives. A substantial effort has been

invested this year in the layout and design of components for CTF2, the upgrade of CTFI to a two-beam test

accelerator for linear collider studies. The designs have been completed and orders placed for quadrupoles for

the 30 GHz modules, high-charge travelling-wave sections for the 3 GHz drive linac, a new 25 cell RF gun


and the micro-movers, tilt meters, and stretched-wire capacitative transducers for the alignment system.

Installation work will start during the 1996 shutdown.

Laser Ion Source Studies

This work moved to new accommodation in building 236, better adapted to the tests envisaged. The laser is

housed in a well-shielded room (the former home of the Cockcroft-Walton set for Linac 2) equipped with a

new safety system, and the laser light is piped to the ion source. A new target vessel has been installed,

together with a Low Energy Beam Transfer (LEBT) section powered by some salvaged supplies. Space has

been reserved for the Radiofrequency Quadrupole (RFO) which will be installed in 1996, and a short analysis

section for the beam after the RFQ. Measurements have been made of emittance, space-charge compensation

and ion yield as a function of laser pulse power and energy density, with encouraging results. The work has

been carried out in collaboration with ITEP and TRINITI in Russia, where the conceptual design report of the

laser that would be needed for LHC was published. This laser would consist of a master-oscillator and laser

power-amplifier. Material tests on the damage threshold of optical elements and tests on the stability of ion

yield for multiple shots at the same target position were carried out.

A new, all-purpose RFQ has been designed and is under construction. It is of the four-rod type with

electrode holders that can accommodate the reserve set of electrodes for the RFQ of the lead-ion facility, for

which it therefore constitutes the backup unit. However, it will also serve as an experimental set-up with

different sets of CERN-made electrodes to cover the different phases of the laser ion source programme. T'he

required flexibility is achieved by a ladder-shaped electrode support housed in a cylindrical shell serving as

vacuum envelope, which allows for easy extension of the whole assembly for higher output energies. It also

simplifies vacuum problems since only standard, cylindrical joints are needed for the end flanges. From the

point of view of beam dynamics, a new approach has been implemented at the entrance section where the RF

voltage on axis (due to the four-rod design) is used for pre-bunching, contrary to normal practice where one

usually tries to suppress the effects of this voltage. In parallel with this work, an existing 200 MHz amplifier

has been converted to 100 MHz, giving an output power limit three times higher than that available from

industrial amplifiers, which is a comfortable margin for the equipment tests foreseen.

The Antiproton Decelerator Study

The way in which low-energy antiprotons are made today involves four machines, the AC to collect them,

the AA to cool and store them, the PS to decelerate them from 3.5 GeV/c to 0.6 GeV/c, and LEAR to further

decelerate them to low energy, then cool and store them ready for use. A simplification of this scheme would

be highly desirable ıf low-energy antiprotons only were to be needed in the future. Simplified ways for the

provision of antiprotons of a few MeV were presented at an ‘Antihydrogen Workshop’ in Munich in 1992.

Subsequently, following the Cogne meeting of the SPSLC in March 1995 on the future of antiproton physics

at CERN, these studies have been updated to take account of the fact that the preferred momentum for transfer

to the traps for antihydrogen production is now 100 MeV/c, and that the use of LEAR as a heavy-ion

accumulator ring has become part of the LHC design proposal so that LEAR has no long-term future with

antiprotons.


A new scheme called AD (for Antiproton Decelerator) has emerged as a proposal which seems to meet the

requirements of the users of low-energy antiprotons. It is based on the use of the existing Antiproton Collector

(AC) ring, to which deceleration, electron cooling, an extraction system, and an experimental area are added.

The advantage of the AD scheme is that it involves only one antiproton ring which is largely decoupled from

the other CERN machines, and makes use of equipment which will no longer be needed once the present

LEAR programme is stopped at the end of 1996. The AD machine and its experimental area are together

housed in the present AAC hall. Following the initial proposal, a feasibility study involving many groups and

experts from PS, MT and AT Divisions was carried out over a very short period in the autumn of 1995. The

conclusion of this study was that the conversion of the AC to an antiproton decelerator is indeed feasible and

would allow a low-energy antiproton programme to be carried out at CERN.

Collaboration with IHEP

UNK Collaboration on Diagnostics

The collaboration between CERN and IHEP on beam diagnostics for the UNK project was not active

during 1995 because of uncertainties regarding UNK and the redirection of IHEP’s efforts to the

U-70 machine.

IHEP Collaboration on Controls

At the start of the collaboration between IHEP (Protvino) and CERN a conceptual design study for the so-

called upper part of the control system for the UNK project was made. In a second stage, some vertical slices

were implemented in order to test the feasibility of decisions taken on the hardware and software side. With

the successful implementation of the computerized control system for the beam transfer line between

U-70 and UNK in 1994, the conceptual studies and prototyping had reached a stage that would have allowed

the proposed solution to be adopted for UNK.

However, owing to a change of priorities at IHEP, it was decided at the beginning of 1995 to first upgrade

the controls of the U-70 complex. This complex, consisting of linac, booster, main ring, fast and slow ejection

systems, target areas and beam transfer lines has no common control system. Its autonomous systems are

controlled from local control rooms situated in different buildings exchanging only a limited amount of

operational information in a non-standard way. A large part is manually controlled, and the computerized

controls are based on obsolete computers. The U-70 controls upgrade project will cover a period of three to

four years. During this time it is intended to establish a uniform control system, based on the so-called

‘standard control model for accelerators’ as used for UNK prototypes in order to make the U-70 complex

more reliable and highly flexible. The new project will profit from the large experience that has been gained in

conjunction with the UNK project. Thus in 1995 the main efforts were concentrated on defining the

U-70 project and writing specifications. Nevertheless, as in the previous years, a number of IHEP

collaborators continued to make substantial contributions to various CERN Divisions in software and

hardware development. In addition, investigations started towards porting EPICS software to the LynxOS

platform.


SPS + LEP Division

Accelerator Physics

LEP Performance

Following the decision made in 1994 to operate LEP with bunch trains, the scheme was commissioned

in 1995 and used in operation until the end of the LEP1 programme. It was also successfully tested in a short

run at 68 GeV. Although initial expectations for a large increase of the luminosity were not fulfilled, the

scheme worked well, finally achieving record luminosities at 45.6 and 68 GeV. The bunch train bumps and the

longitudinal bunch separation were designed to operate with four bunches per train. However, the residual

beam-beam interactions at parasitic crossings caused the individual bunches to travel on different closed

orbits. In particular, the last bunches of the trains collided with a sizeable vertical offset and its effect on the

luminosity was stronger than expected. A newly developed program, TRAIN, allows a self-consistent and

precise calculation of these offsets. In addition, measurements revealed that, as predicted by multibunch beam

break-up theory, transverse oscillations of the first bunch were driving the following bunches to larger

amplitudes. To alleviate the detrimental effects of these two phenomena, LEP was operated for most ofthe Z

physics period with only three bunches per train. In this situation the beam-beam tune shift was around 0.03.

In an experiment with only two bunches per beam, performed towards the end of the period, it was raised

above 0.04. This latter configuration is favourable for LEP2 in which the two phenomena mentioned above

become unimportant.

During the 68 GeV operation period the vertical-to-horizontal emittance ratio was reduced to around 0.5%.

This gives confidence that the beam-beam limit can be reached in LEP2.

LEP2 Studies

The design of the bunch train scheme for LEP2 was studied, and a proposal to modify the bumps and

bunch spacing was made. A lattice with a phase advance of 108 degrees in the horizontal plane and 60 degrees

in the vertical plane was rematched to be compatible with bunch trains and tested in the machine.

A preliminary study showed that an optics could be constructed with the new layout of quadrupoles

necessary for the installation of the additional superconducting cavities of LEP2 Phase IV.

With the availability of the new superconducting cavities a very high synchrotron tune O, could be used at

injection. With a Q, of about 0.16 it was possible to inject about 1 mA in a single bunch, a value very close to

that predicted by theory using the current model of the LEP transverse coupling impedance.

SPS + LEP Division

The wakefield tables for the various components contributing to the LEP impedance were updated

following the installation of new equipment. These were used in the simulation program TRISIM to study the

vertical Transverse Mode Coupling Instability (TMCI) thresholds in different conditions of bunch length and

Q,, and to optimize the parameters of the reactive feedback system. The program TRISIM was further

developed to include coupling between horizontal and vertical planes by either solenoid and skew magnetic

fields or by wakefields generated by axially asymmetric structures. The tensor coupling impedance required in

this case is computed with mesh codes in three dimensions.

At its highest energies LEP will enter a regime where single-particle dynamics are dominated by strong

synchrotron radiation effects. These lead to substantial differences in closed orbits and optical functions

between the two beams. Theoretical studies of these effects continued and were compared with initial

experience at 65 GeV.

The radiation also increases the phase space volume occupied by the beam, demanding more dynamic

aperture. The understanding of the physical effects limiting the dynamic aperture at high energy was deepened

with the help of improvements in analytical and computational methods. A number of possible means to

increase the available dynamic aperture were studied. Among these, a new optics with betatron phase advances

of 108 degrees horizontally and 90 degrees vertically gives promising results. Experimental measurements of

the dynamic aperture were in quantitative agreement with predictions. The additional prediction of a higher

TMCI single-bunch intensity limit due to the smaller vertical betatron function was also borne out

experimentally.

Polarization

To calibrate the beam energy in LEP2, transverse polarization is needed at the highest possible energy.

Studies were pursued to calculate and maximize the degree of polarization at energies of around 60 GeV. This

appears to be the highest favourable energy window for calibration through resonant depolarization.

LHC Studies

Version 4.1 of the LHC lattice, which uses three bending magnets, each 14.2 m long, per half-cell, was

finalized. It has the advantage over previous versions that the dispersion suppressors now contain the same

bending magnets as the arcs. This was achieved without significantly perturbing the geometry. A new service

insertion was designed in straight section 4 to house the RF system. This insertion could, in addition, be

equipped later on with an experiment if required.

The dynamic aperture of version 4.1 was compared to the previous versions in the same conditions of field

and alignment imperfections. As expected, lengthening the cells reduces the dynamic aperture. However, the

present value reaches 96 where o is the transverse r.m.s. beam size at the maximum of the betatron function in

the arcs. This is still considered acceptable.

The reduction in dynamic aperture produced by slow tune modulations due to power supply ripple was

investigated with special tracking simulations lasting over 10° turns. With a ripple amplitude and frequency

spectrum analogous to those measured in the SPS the aperture is reduced by about 10%. Work has started to

evaluate the ripple characteristics in the LHC by measuring the transmission properties of the magnet lines.

SPS + LEP Division

After this base-line design was made available, studies turned to the evaluation and improvement of the

flexibility and robustness of the lattice. Since the insertions are optically antisymmetric, the correction of the

dispersion created by the recombination dipoles imposes rigid constraints on the matching of the insertions. It

. was shown that this can be cured by adding a few weak quadrupoles in the cells at the extremities of the arcs.

The focusing and defocusing quadrupole chains of the two rings are powered in series. To correct

individual focusing perturbations in each ring a third bus bar provides an additional trim excitation. After a

careful estimate of the perturbations, it was shown that the two rings could be individually tuned using the

small quadrupoles mentioned above and the trim bus bar could be suppressed.

The chromaticity correction scheme was re-examined for the new lattice version taking into consideration

realistic operational requirements. The strength of the sextupoles is sufficient for all cases considered.

Powering them in two families is adequate for the present LHC design. However, it has been shown that

increasing the number of families from two to four would allow the vertical beta function at the interaction

points to be reduced to 0.25 m in the future.

In parallel studies, an effort was launched to develop the tools needed for more efficient design work. New

facilities were introduced in MAD. These include the ability to optimize the geometry as well as the optics.

This will allow the LHC geometry in the LEP tunnel to be more finely adjusted. The input language of MAD

was improved to provide a structured and faster description of the LHC, including imperfections. Such a

description serves as a starting point for the LHC database. Special features were also introduced in MAD to

accelerate the evaluation and optimization of dynamic aperture. In addition, an interface between MAD and

SIXTRACK, an independent simulation program, was developed to allow results to be cross-checked.

A systematic revision of the LHC impedance budget is in progress and an integrated computer code for

beam dynamics calculations, coupled to an impedance database, is being developed. Estimates of parasitic

losses, tune shifts, and instability thresholds corresponding to the latest design options were published in

the 1995 LHC Conceptual Design Report.

A critical review of resistive losses in the LHC beam screen, taking into account the anomalous skin effect

and surface roughness, was performed. A programme of surface resistivity measurements at different

temperatures, frequencies, and magnetic fields was launched to refine the estimates for the heating budget of

the LHC cryogenic system. Work progressed on the evaluation of magnetic Laslett coefficients in the LHC

geometry and transient space charge effects including field penetration in a resistive wall.

The phenomenon of longitudinal beam echoes, which could open new perspectives for diffusion and

impedance measurements in proton machines, was investigated theoretically and tested experimentally in the

SPS.

Detailed simulations of the beam cleaning insertion, combining particle scattering in collimators and

multiturn tracking, allowed a precise evaluation of the collimator efficiency. The efficiency is more than

enough to prevent magnet quenches in normal operation. By combining studies of the shape of the secondary

beam halo which emerges from the cleaning system, and of detailed mechanical tolerances around the

machine, it was shown that the square cross-section of the beam screen was not the best solution. A circular

section with flat parts at the top and bottom to accommodate the cooling tubes is now preferred.

SPS + LEP Division

Beam-beam tune footprints of colliding beams were evaluated for LHC version 4.1. Calculations

confirmed the conclusions of a previous study that two beams crossing at an angle of 200 urad in a plane

inclined at 45 degrees to the nominal transverse planes would experience less overall long-range tune shifts

and tune spread than with alternative crossing schemes. Operation in such a regime, which is dominated by

short-range (head-on) effects, is interesting because the effect of the so-called Pacman bunches is significantly

reduced. Such a crossing is achieved with a set of horizontal and vertical orbit correction dipoles placed

outside the part common to the two beams. These allow the two beams to be moved in a spherical region about

the nominal interaction point to maximize luminosity or lifetime.

Different algorithms to compute the betatron tune with a high precision in a small number of turns were

studied. They are used in tracking studies and were tested experimentally in LEP. Fast indicators to evaluate

the dynamic aperture after tracking for only 10° or 10% turns were systematically investigated. The aim is to

use them to order the magnets during installation, alleviating the effect of random magnetic errors.

The experiments at the SPS to study the feasibility of extracting protons using a bent crystal were

continued. A novel design of the crystals proved the existence of the multipass extraction mechanism and led

to high extraction efficiencies.

Siberian Snakes that act as spin rotators have been studied for the e-p option of the LHC.

CLIC Studies

By recalculating single-bunch parameters, the predicted luminosity was increased while keeping

acceptable beamstrahlung characteristics and background conditions. The small vertical emittance required

was obtained by introducing a particularly powerful correction method based on direct measurements of

dispersion and wakefield effects.

Investigations were launched to test methods of controlling the emittance of multibunch beams which

becomes necessary to reach the new luminosity goals.

The interaction region was redesigned for multibunch beams to allow for a horizontal crossing angle. A

small-angle scheme was studied where the outgoing beam passes through the same beam hole in the low-beta

quadrupoles as the incoming one. A solution with acceptable parasitic beam-beam kicks could be found with

slightly enlarged, unequal apertures in the permanent magnet quadrupoles of the final doublet. However, it is

sensitive to a vertical ‘kink’ instability.

A possible design for an isochronous three-bend achromat was developed and proposed as a module to be

used in the 360 degree bends and possible rings that are needed in the injection schemes for the main and drive

beams. These achromats preserve short bunches and limit emittance growth due to radiation.

Three separate tracking programs were developed for the study of the multibunch drive beam. These

simulate beam break-up control through strong variable focusing, estimate losses associated with transverse

deflecting fields, and deal simultaneously with space charge forces, wakefields, and wave propagation.

SPS + LEP Division

Beam Instrumentation

SPS Fixed-Target Operation

Fast diagnostics for the extracted beams were completed and have helped to provide a better spill quality to

the experiments. The studies on secondary emission efficiency were pursued with aluminium and titanium

foils in order to give more precise information on particles delivered to the experiments. It was shown that

titanıum foils are more stable and they will be used in future whenever possible.

The consolidation programme for the orbit measurement system (COPOS) started well. The construction

of 300 filters and calibration units was contracted out to the CERN-TRIUMF Collaboration. The prototype

card for the turn-by-turn data acquisition works satisfactorily. The difference between orbits measured with

electrons or positrons was reduced considerably with a revised calibration procedure. This allows better

optimization of the electron injection into the SPS.

Two current transformers installed in the TT10 transfer line were equipped with a new readout system

based on a commercial fast digital oscilloscope, this allowed the measurement of the heavy-ion transmission

efficiency.

The fast tune measurement system (MULTIO) is now used to monitor lepton beams throughout the whole

acceleration cycle. It uses a white noise excitation and sliding FFTs for data analysis. During a machine

experiment a chirp excitation was successfully used for MULTIQ measurements with a proton beam.

The upgrade of the control system in the SPS Experimental Areas required exhaustive testing of the new

layers of software which finally led to asmooth restart of all facilities. A new type of beam profile monitor that

is vital for ion physics runs was put into operation.

LEP

The beam orbit measuring system worked satisfactorily for closed orbit correction and for machine optics

studies. In order to measure the positions of individual bunches in trains, the wideband electronics used for the

pick-ups near to the IPs were adapted to work with a new external triggering. Using this facility, beam

positions measured near the IPs were logged systematically during physics data-taking. An analysis made by

physicists from the four experiments showed that the vertex position deduced from those measurements will

be useful, and indeed essential, for physics done at LEP2.

A new software facility was introduced allowing an equal filling of bunches in trains during the injection

phase and has proved extremely efficient. It was based on bunch current readings that were performed with a

new acquisition system needed to observe bunches separated by only 247 ns.

The wire scanner and synchrotron light telescopes were improved so that emittances could be measured

down to 0.2 nm. During the year, the main uncertainty about measured emittances came from inaccurate

knowledge of the machine optics functions. The carbon wires of the wire scanner were replaced by quartz

wires that increased the current limit from 1.8 mA to over 8 mA.

SPS + LEP Division

A multipurpose timing circuit, with picosecond resolution and jitter, was developed. It will be used by

various instruments that need to be accurately synchronized to the beams. It enabled the lengths of up to four

different bunches per train to be measured simultaneously with the streak camera.

A new type of horizontal collimator was designed to replace the double horizontal and vertical collimator

located at 8.5 m from the IPs. This will make room for the small-angle detectors of the experiments. Thirteen

new collimators were installed to improve the background in the experiments.

The second period of the 1995 LEP run was dedicated to a two-point energy scan around the Z peak.

Among the many effects influencing the LEP beam energy, which induce variations of the centre-of-mass

energy, two in particular are new for the 1995 run. Online use of NMR probes inside two LEP dipoles in the

tunnel showed an unexpected rise in the main magnetic field during experimental fills corresponding to an

effective energy change of about 5 MeV. This effect was traced back to small electric currents flowing along

the vacuum pipe that originate in leakage from the rails of a nearby railway line. No cure for this effect is

currently envisaged. Systematic centre-of-mass energy changes at the four IPs caused by residual vertical

dispersion and small collision offsets when operating LEP with three bunch trains were predicted, successfully

simulated, and found to be in good agreement with the measurements. The strategy proposed by the LEP

Energy Working Group to minimize the centre-of-mass energy shift was applied with the regular use of the

vernier scans throughout the whole 1995 energy scan.

LHC

Studies of different types of monitors were pursued and a proposal made for ‘A new diagnostic for betatron

phase space matching at injection into a circular accelerator’.

Stripline monitors to measure beam positions underwent further detailed studies and a schedule was

established for their fabrication, testing, and installation in the short straight sections by the French

Collaboration for LHC.

Beam Transfer

SPS Operations

The delicate operation of replacing the irradiated part of the 54 coaxial high-voltage cables feeding the

SPS proton and positron injection kicker was completed during the annual shutdown. The system was ready in

time for the restart of the SPS.

The pulse generators of the electron and positron extraction kickers were equipped with novel two-stage

thyratrons which allow safe operation at the increased LEP injection energy.

The target station (T9) for the neutrino experiments CHORUS and NOMAD continued to operate

very reliably. Endoscopic examinations of the beryllium rods showed no signs of damage. Further calculations

on their thermal and mechanical behaviour confirmed the maximum tolerable beam intensity of

SPS + LEP Division

1.5x 10"? protons per fast resonant extraction. During the two years of operation the target received more than

2x 101° protons at 450 GeV, with peak intensities of 2.8 x 10" per SPS cycle.

The total number of protons extracted increased from 11x 1018 to 19 x 10! and the average accelerated

proton intensity increased from 2.28 x 10° to 3.22 x 10". Despite this the operation of the extraction

channels was much smoother than in previous years. This was mainly due to a better control of the beam

during capture and acceleration resulting in fewer protons being lost from the RF buckets during ramping.

Over the year, only one feedthrough, in the first electrostatic wire septum (ZS) in LSS6, was damaged by

sparking following a short machine development session.

For the ZS the spares’ situation is alarming. The surface treatment of high-voltage components was

contracted out by MT Division, but the resulting performance was unacceptable. Efforts must be made in 1996

to ensure efficient replacement of faulty equipment. The spares’ situation for the magnetic septa is adequate.

Several faults developed on the shutters. These required machine interventions. A new design of shutter,

intended to prolong the lifetime and increase reliability, is currently under development.

Several improvements were made to the extraction channels. High-capacity regeneration stations were

installed for the treatment of the dielectric liquid used in the high-voltage feedthroughs. These stations have

reduced the necessity of maintenance work during operation, which previously involved high radiation doses

to the personnel. In fact, the total radiation dose to the personnel dropped from 120 mSv to around 40 mSv.

The installation in the Pr&evessin Control Room (PCR) of fixed displays showing spark rates and beam loss

improved the surveillance of the extractions by the operators, and resulted in a reduction in sparking and faults

during operation. Analysis of beam loss and induced activity made significant progress, with better

understanding of induced doses and the possibility of predicting radioactivity levels from the beam intensity.

LEP Operations

The LEP start-up in 1995 was with the full bunch train configuration i.e. with 40 operational vertical

separators. The transformation of the separator system involved the installation of eight new separators in the

even IPs, and the displacement of eight separators in the odd IPs. In addition, the polarity of over half of the

installed tanks was reversed. This required a full series of reconditioning and tests. The pretzel separators will

remain in LEP until the bunch train scheme is fully accepted. This would allow a return to pretzel operation

with a minimum of machine intervention. However, the two pretzel trim separators have already been removed

and transformed into prototype vertical ZY separators (which could be necessary for LEP?2).

The separator performance with bunch trains was generally satisfactory. However, repeated sparking in the

ZLS8 separators in IP3 could only be cured by operating with voltage on the positive plate only. In IP2 and IP6

the bunch train bump amplitude had to be reduced to 70% because of sparking in the ZL4 separators. At the

end of the year, the increase of the LEP energy to 65 and 68 GeV did not produce any significant increase in

separator sparking. In fact over this period only one spark was observed. Although the bunch train bumps in

the even IPs during this period were reduced to 20%, the full bumps were used in the odd IPs.

SPS + LEP Division

Research and development into prototype insulators for the LEP separators identified a promising ion-

implantation treatment of existing alumina insulators that, in the laboratory, reduces UV-induced sparking by

an order of magnitude. At present full-scale prototype insulators are being assembled for installation into LEP

separators in IP3, ready for the 1996 start-up. In addition, prototype ceramic insulators of a completely new

type are being developed by a second collaboration.

For the central injection kickers a facility for polarity reversal was installed to allow injection at machine

tunes with phase advance above 90 degrees. It consists of a 20 kV pulse transformer in combination with a

remotely controllable high-voltage relay.

LHC Activities

Studies of alternatives for the LHC injection transfer lines were continued and a final version was adopted

which uses room-temperature magnets for the two lines, TI2 and TI8, that lead from the SPS to the LHC. For

TI8, provisions have been foreseen to allow the construction of a neutrino beam-line for long baseline neutrino

experiments i.e. towards a detector at the Gran Sasso Laboratory in Italy.

After the successful test in 1994 of a prototype extraction kicker for the beam dump system, the effort

in 1995 concentrated on testing alternatives to the thyratron switches of the pulsers that have the very

undesirable feature of producing erratic firings. Among the possible alternatives a semiconductor switch

received particular attention. An assembly of high-power gate turn off thyristors produced very encouraging

results. Progress was also made with the pseudo spark switch where the quenching at low-voltage operation

was suppressed by the use of another gas mixture and where the absence of prefiring was confirmed by

extended test runs.

The work on energy deposition, on thermal and mechanical behaviour, and on radiological problems was

- continued with a view to finalizing the dimensions of the main absorber of the LHC beam dump system.

The design of the LHC injection kicker was started. In order to achieve the required very small flat top

ripple, extensive computer simulations, taking into account the influence of parasitic components, were

performed in collaboration with a Canadian team. It is intended to start construction of a prototype in 1996.

Electronics and Equipment Control

The electronic and control systems for the extraction channels, electrostatic separators, and kicker magnets

worked very reliably. In addition to numerous small hardware and software improvements for the control of

the different SPS and LEP systems, the following issues received key attention:

— the modernization of the second part of the electronics of the SPS beam dump kicker;

— the regulation of the resonant extraction kicker pulse shape;

— the standardization of the LEP separator control from the high- to low-level software, including the

rewriting of the user interface and the automatic conditioning programs within the framework of the TS

Toolkit;

SPS + LEP Division

— the improvement of the machine timing events broadcasting;

— the continuous logging of the generators’ status to the central LEP measurement database;

— the real-time surveillance of the SPS extraction channels using Oracle database techniques and fixed

displays;

— the specification of, and a market survey for, a wave form acquisition, surveillance, and diagnostic

system for the LEP injection kickers, in order to contract out the complete project to industry.

Controls

Experimental Areas

In 1995 the new control system for the SPS Experimental Areas was completed and put into operation.

This was the culmination of four years of careful planning and hard work by members of the CO, BI, and EA

groups. The old control system for the Experimental Areas, which was based on NORD-100 computers, had

given excellent service for 15 years and its facilities had been greatly appreciated by the users. However,

certain parts of the system, particularly the NORD computers, were becoming difficult and expensive to

maintain. The NORD computers were also being replaced in other parts of the control system. An upgrade of

the Areas control system was therefore essential.

The old control system was based on serial CAMAC. As such there is a large investment in CAMAC and

dependent equipment. Thus it was necessary to keep as much of the low-level layer as possible while replacing

the NORD computers with a modern computer system. There was also a very large investment in application

programs that had been written over the 15-year life of the old control system. Many of the original engineers

and technicians who had written this software were no longer available to help with the upgrade.

In the new control system, the old NORD computers were replaced by HP-UX workstations. The long-

range communication in the zones, which had been performed by serial CAMAC links in the past, was

replaced by Ethernet links to small front-end computers (FEs). These FEs perform local surveillance of, and

general access to, the CAMAC crates. Software was written which duplicated the intermediate software layers

that had existed in the NORD computers. The application programs themselves were written in the

interpretative language NODAL. A NODAL interpreter, written by the control group of the PS Division, was

adapted for use in the Areas.

The connection of the CAMAC crates to the new system was done with new crate controllers. These could

be configured to work either as main controllers or as auxiliary controllers. They were initially installed in the

auxiliary configuration. This meant that the new control system could be used to control the zones without

removing the old control system, an arrangement that was invaluable for testing.

As more of the intermediate software layers were completed, extensive tests were performed on the

equipment in the zones. Careful liaison between the CO, BI, and EA groups was necessary to ensure that these

tests took place without perturbing the experiments. The advice and help of the SPS physics co-ordinator were

invaluable during this test period.

SPS + LEP Division

The old control system was finally removed during the 1994/95 shutdown. The start-up of the zones was

performed using the new system. The beams were tuned and ready for the experiments two days before the

scheduled time. The subsequent operation was remarkably trouble-free. The new control system must be

considered a complete success, and a tribute to the co-operation between the groups involved. This

achievement marks the final retirement of the NORD minicomputers and the TITN network from the SL

control system. These were first introduced for the control system of the SPS in 1975 and formed the basis of

all SPS control until 1994.

Other Upgrades

Other upgrades and rationalizations were pursued this year with the goals of increasing reliability and

simplifying maintenance. In the FEs the major improvement was the introduction of a new generation of

MIL 1553 bus controllers (NBC) for both the PC and VME standards. These NBCs replace the complicated

and expensive parallel PC-VME connection. The SPS machine front ends are now 486-PCs running Lynx-OS

with up to four NBC PCs and their associated buses. This simplification was the major reason for the reduction

of controls-related machine downtime from 117 hours in 1994 to 25 hours in 1995.

In the control room layer the first stage of a project to phase out the Apollo workstation was completed.

The machines were selected in the mid-eighties as the platform for the LEP machine and all SPS

developments as the LEP injector. In 1995 the Apollo service was discontinued to all laboratories, offices and

remote buildings. This simplification allows the improvement of the networking support for the accelerators.

Freed from the need to support Apollo networking one can benefit from later releases of networking software

from the suppliers.

Work is under way to upgrade the LEP machine network backbone from a 4 Mbit/s token ring to a

100 Mbit/s FDDI. During the early part of the year optical fibres were pulled through the drains beneath the

LEP tunnel to provide high-speed links to the pit bottoms and alcoves. Work was hindered by obstructions in

the region passing under the Jura, but points 1, 2, 4, 5 and 6 were controlled via the new backbone from the

spring start-up. This work is essential to keep pace with the increasing network traffic generated by the large

number of new machines being installed for the control of LEP2. At the same time it follows the continuing

trend towards distributed computing.

Application Software

It has been a year of consolidation for the control room application software. The statistics and fixed

display systems were extended and the performance improved at all levels. This was accompanied by

improved hardware and the SL performance screens are now available live on the Web. After intensive

development activity over the past two years an entirely new suite of software for the control of all SL external

beam lines is being introduced. The first application to be commissioned was the TT10 injection line from the

PS to the SPS. The new software provided important new possibilities that contributed to the successful

physics run this year.

SPS + LEP Division

Experimental Areas

West Area

The West Area test facility with its four versatile and popular test beams X1, X3, X5 and X7 was heavily

used during the year. A substantial fraction of the programme focused around R&D activities for future LHC

detectors. The electron versions of the X1 and X3 beams saw a number of different tungstate crystal detectors

with associated electronics being tested. High-resolution and high-luminosity silicon and diamond detectors

took much of the X5 beam time, and tracking studies for CMS were performed with the X7 beam.

The test facilities of the West Area are also still frequently used by the LEP and fixed-target experiments.

L3 and OPAL used the X3 and X5 beam, respectively, while DELPHI, CHORUS and NOMAD profited from

both the X5 and the X7 beams.

The X7 beam had to be constrained to run at low positive momenta in order to limit muon backgrounds

into the emulsions of the neutrino experiment CHORUS. Nevertheless the beam was used for a variety of tests

by a number of different groups. The CHORUS Collaboration also used the prolonged version of this beam,

the so-called X9 variant, for calibrations and tests.

The West Area proton physics programme continued vigorously this year with a full employment of the Hl

beam line and the associated Omega spectrometer. To start with, 450 GeV/c primary protons were delivered to

the WA102 Collaboration for a search for exotic mesons. Later the beam was transformed into the secondary

particle mode to supply the experiment WA97 with 160 GeV/c pions and protons to prepare their detectors for

the lead-ion run. In the shutdown between SPS proton and ion operation, splitters were again introduced in the

TCC6 target area and both the Hl and H3 beams were transformed to transport lead ions of 32.8 TeV energy

per ion.

The lead ions were used by the WA97 Collaboration in Omega for a continued search for strangeness

enhancement in high-energy nucleus-nucleus interactions. The WA98 installation, comprising both a charged-

particle spectrometer and a number of different detectors for neutral particle detection, was further enlarged

during the year and was ready in time to receive the ions in the H3 line.

The H3 beam line itself was also used as a heavy-ion spectrometer during a two-day period by the WA99

Collaboration to collect data on charge-changing collisions, energy loss, and electromagnetic nuclear

reactions.

North Area

In the North Area Hall EHNI, the H2 beam was intensively used by the LHC CMS Collaboration to

provide, alternately, hadrons, muons, and electrons, mainly for the development of their hadron calorimetry

and muon detectors. The crystal experiment NA43 again used a highly parallel beam of electrons either

directly or as a source of tagged photons to study electromagnetic processes in orientated crystals. These

included measuring the enhancement of pair-production by photons in a crystal of iridium, which has a

potential application in the CP-violation experiment NA48. Protons with momenta as low as 6 GeV/c were

SPS + LEP Division

derived for the first time from A-decay to calibrate the time projection chambers of experiment NA49, which

then went on to record data throughout the successful period of running with lead ions at the end of the year.

The H4 beam was also exploited by CMS to develop both hadron and electromagnetic calorimeters using

electrons, hadrons, and muons over a wide range of momenta. The programme to test the read-out electronics

on a prototype liquid-krypton calorimeter for experiment NA48 was completed, using a beam of electrons.

Primary protons were used by the NA44 spectrometer to set up and take data for comparison with those

accumulated during the lead-ion run. With improved shielding, the intensity of this beam was doubled

compared to 1994.

The H6/H8 beam complex is gradually evolving towards being the major ATLAS test and calibration

facility for electromagnetic and hadronic calorimetry, tracking, and muon chamber tests. It will also act as an

ATLAS ‘slice’ test. The majority of the beam time in H8, as well as some time in H6, was devoted to ATLAS

tests. In addition, the H6 beam was also used for a variety of smaller generic R&D projects, for tests related to

various CERN experiments, and for the continuation of the NA52 ‘strangelet’ search experiment. The H8

beam was used by the modified NA45 experiment which had a successful run with lead-ion beam. The tests on

the beam deflection properties of bent crystals were continued using the H8 micro-emittance beam and a bent

germanium crystal as well as a strongly irradiated silicon crystal. First results were obtained on the

impairment of the beam transmission due to irradiation of the crystal.

In the high-intensity hall ECN3, two one-month periods were devoted to setting up and first data-taking of

experiment NA48, using the P42 primary proton beam to produce neutral kaons in the K12 beam line. The

complete spectrometer was installed to detect the charged-particle decay modes of the long- and short-lived

neutral kaons. The derivation of the simultaneous beams relied on the novel functioning of a bent, silicon

crystal.

During the remainder of the proton time, as well as during the full lead-ion period, the P41/P61 beams

were used for setting-up and data-taking by the NA50 dimuon experiment. One eight-hour period was devoted

to a first test run of P288—-a search for monopoles and ultradense nuclear matter.

The M2 high-energy muon beam served the NA47 experiment as main user for measurements of

longitudinal and transverse polarization effects in nucleon structure functions. Parasitic users of the beam

included the NA54 experiment, feasibility studies for a possible future experiment P293, and tests for ATLAS

and NESTOR.

LEP

During the 1995 physics data-taking runs, machine backgrounds to the experimental detectors were often a

limiting factor in the luminosity performance. The limits were due to large spikes, predominantly in the

photon background rate, which often resulted in a trip of the high voltage in one or several central chambers in

the experiments. The signal in gaseous detectors from synchrotron radiation photons is a very sensitive

indicator of instabilities in one of the transverse planes of the LEP beams. It is believed that such instabilities

are the origin of the background spikes. The dynamic origins of the observed beam instabilities are not

completely understood.

SPS + LEP Division

Machine-induced particle background to the detectors during stable beams, however, was normally

acceptable and very low during the high-energy runs. Detailed studies had shown that the vertical separation

bumps with bunch trains can produce very high additional photon backgrounds. These studies, backed up by

machine development measurements, allowed the development of means to control the additional bunch-train-

induced background to within tolerable limits.

The OPAL luminosity detectors were hit during the first part of the energy scan by off-energy electrons and

positrons with very specific energy and spatial signatures. This background seriously limited the precision of

the OPAL luminosity measurement. These off-energy particles were finally understood, using Monte Carlo

simulations, to be again due to the presence of the bunch train bumps. As a consequence they could be

sufficiently suppressed during the second part of the energy scan by reducing the bump amplitudes in OPAL,

and by closing tighter horizontal aperture limits.

As predicted by simulations, photon backgrounds were low at 65 GeV because the increased rate due to’

higher beam energy was counter-balanced by the very small beam emittances.

A dedicated machine development experiment, involving all four LEP Collaborations, demonstrated the

correct functioning of the two synchrotron radiation masks which are now installed in the DELPHI and OPAL

interaction regions. Synchrotron radiation masks will be in place in all four experiments for high-energy

running in 1996.

Main Ring

SPS

During the 1994/95 shutdown, the SPS Access system was replaced by a new turnkey system bought from

Technost, a part of the Olivetti company. The project was not completed during the long shutdown as was

initially planned and work continued throughout the year as far as was possible given restrictions imposed by

the operations schedule.

Irradiated cables were changed in sextant 1 as part of the continuing campaign which is carried out

annually during the long shutdown. Five main bending magnets were replaced in the shutdown, together with

six main quadrupoles. A further four main bending magnets were changed during the rest of the year. Again

during the shutdown, a superconducting 350 MHz RF cavity was exchanged, and a 400 MHz LHC test cavity

was installed, both in LSS4.

At the end of the year, following the heavy-ion run and prior to the Christmas break, roughly 10 days were

reserved with the SPS closed without beam for equipment tests. Despite critical days, tests were carried out on

the main and auxiliary magnets, the power converters, the RF, the emergency stops, the smoke detection and

evacuation systems, etc. This period proved extremely useful and should definitely be repeated in future.

In parallel with the end-of-year test period, the ECA 5 pit (ex UAI garage) was made ready for the

installation of ATLAS equipment for alignment tests.

SPS + LEP Division

LEP

The major machine modifications made during 1995 were associated either with the bunch train mode of

operation or with the LEP2 upgrade.

The bunch train project required additional separators in the even points, and a displacement of the outer

separators in the odd points. Points 4 and 8 had already been equipped for bunch trains during the 1994

technical stops, points 2 and 6 were completed in 1995. Pretzel sextupoles in points 1 and 5 were converted

for use with bunch trains and repositioned. Several other modifications to the LEP layout were necessary,

including the repositioning of the skew quadrupoles. Three pretzel separators in points 2, 6, and 8, and one

vertical separator in point 4, were removed.

The final LEP2 configuration was realized in point 6 with the replacement of the superconducting

quadrupoles by a stronger version, and the repositioning of the skew quadrupoles. Large-aperture vacuum

chambers were also installed, as were additional collimators. A total of five superconducting RF modules were

added during the shutdown, one in point2 and four in point6, where a module was also removed.

Superconducting cavity protecting collimators were installed in points 2, 4, and 6; point 8 having been

equipped in 1994,

During the June technical stop, two more superconducting RF modules were installed in point2 and a

further two in point 6. This included the one that had been removed in the long shutdown. The October

technical stop saw the installation of four superconducting modules in RA 87 making a total of twelve extra

modules for 1995.

The laser interaction region in point 1 was moved so that the polarimeter could function equally well for

both positrons and electrons, and with the bunch train bumps.

Realignment of the whole machine was carried out in the vertical plane. Realignment in the horizontal

plane took place to the right of point 8 and to the left of point 3.

Throughout the year, a general campaign of site improvement on the surface was carried out with special

concern for aspects of site access security, for example an automatic gate was installed at point 7. Progress

was also made in the area of noise reduction.

Control of the physical conditions (humidity, temperature, etc.) is a permanent concern in the LEP tunnel,

and 1995 saw improvements to the ventilation situation with the installation of supple sliding doors. Humidity

problems in the electricity ‘safe rooms’ were overcome by the introduction of air conditioners.

Visitors to the LEP tunnel are becoming more and more numerous. Consequently, ever increasing

assistance is required, notably from the LEP site managers.

SPS + LEP Division

Operations

LEP

LEP operation in 1995 had to meet several goals. Firstly, LEP2 superconducting RF modules in ever

increasing number were used during the physics programme. Secondly, the bunch train scheme, following

successful tests the previous year, was used throughout. Thirdly, although not finally decided until late June,

several weeks were devoted to a scan in energy around the Z" resonance, with careful monitoring of a wide

variety of machine parameters and frequent calibration of the beam energy. Finally, after installation of more

superconducting RF modules in October, the last few weeks of operation were at the highest attainable energy,

with 70 GeV the absolute maximum possible.

On top of the many modifications to the machine for the LEP2 RF cavities and the bunch train scheme,

other changes had to be accommodated. The cooling system was upgraded in preparation for the extra load of

running LEP at higher energies. Around point 6 the final LEP2 layout was installed, involving the installation

of new superconducting quadrupoles, installation of a large-aperture vacuum chamber and the relocation of

skew quadrupoles. Collimators to protect the superconducting cavities were installed in points 2, 4, and 6. The

laser interaction region used for polarization had to be moved to cope with bunch train bumps. Finally,

synchrotron injection was used from the start. This later allowed eight bunches in a single SPS cycle to be

injected into four equidistant bunches in LEP.

In spite of all these changes the machine start-up was again very efficient, with the first collisions for

physics on 3 May, some ten days after first beam was injected. The first physics runs were with four positron

against four electron bunches, during which several operational problems were resolved. Notable among these

were radiation problems during accumulation, and photon backgrounds during physics. These effects were

due to the bunch train bumps around the experiments, and were successfully suppressed by a combination of

reduced electrostatic bumps, superimposed magnetic bumps, and the use of collimators.

Bunch train running began on 6 May, with four trains of two bunches per beam. LEP operation continued

in this mode until 18 June, by which time further difficulties connected with bunch trains had been mastered.

A few physics runs were then made with trains of three, before moving to the full scheme of trains of four for

the last week before the technical stop, scheduled from 26 June. Operating LEP with four trains of four

bunches per beam proved to be very difficult. Parasitic beam-beam effects cause fundamental differences

between bunches in a train, and it was rare that the full 32 bunches could be ramped in energy, squeezed, and

put into collision.

The second operational period, from mid-July to early October, was devoted to an energy scan, running

with different centre-of-mass energies close to the Z? peak. In light of the difficulties encountered when

running with four bunches per train, it was decided to opt for the more stable scenario of trains of three.

Several other machine parameters were fixed in the interest of providing the most reproducible conditions

during the scan. A few measurements were required on a regular basis during physics. Twice in every fill

systematic scans of the vertical crossing were made in order to minimize errors arising from any offset in the

orbit of the bunches. On the end of each off-peak fill a calibration of the beam energy, using the technique of

resonant depolarization, was attempted. On several occasions such an energy calibration was also made at the

start of the fill. A multitude of machine parameters were measured and logged for post-correction of known

effects.

SPS + LEP Division

Machine performance improved gradually through the first half of the scan and remained smooth

thereafter. Single-bunch currents were typically 0.35 mA, similar to those collided with the pretzel scheme.

With 12 bunches per beam instead of 8 the maximum total current in physics was over 8 mA. Besides

providing more intensity for physics, these high currents proved very useful in testing the new RF units and

their couplers. Despite the higher current, however, the instantaneous luminosity was comparable to that

of 1994 because the beam-beam parameter did not exceed 0.03, compared with values up to 0.045 in the

pretzel scheme. This resulted in peak luminosities in the experiments of a little over 2 x 10°! cm? sl. During

the scan, the overall efficiency was also similar to 1994, with 60% of the scheduled time for physics being

spent in coast for either stable physics or energy calibration.

The integrated luminosity during the period of the scan was distributed as follows:

— peak-2GeV 10.2 pb’! of which 79% was successfully calibrated at the end of fill

- peak 5.7 pb!

— peak +2GeV 10.3 pb-! of which 72% was successfully calibrated at the end of fill.

Together with the 13.7 pb’! accumulated at the peak before the scan started, this amounts to a total

delivered luminosity to the experiments of 40 pb! during the year for z physics.

During the October technical stop LEP was prepared for runs at energies higher than 45 GeV,. This entailed

changes to power converters, magnet calibration curves, cooling, and the installation of more superconducting

RF cavities. Furthermore it was decided to fill LEP with an injected beam energy of 22 GeV, in order to benefit

from the 10% gain in single-bunch current that this had been shown to yield during machine development.

Commissioning for high-energy running began on 27 October, and within four days the world’s first

physics with colliding e*e” beams at 65 GeV took place. The luminosities were of the order of 10°! cm? st.

The newly installed superconducting RF cavities imposed a maximum current limit of 4mA for most of

the period, and operation was consequently with four-positron against four-electron bunches. LEP ran at

65 GeV for the first half of the four-week period, with initial Iuminosities frequently between 2.5 and

3.0 x 10°! cm”? s!, There followed a short period of running at 70 GeV, which proved difficult as the RF

system had no margin for safety, a single unit trip causing loss of the beam. The energy was therefore reduced

to 68 GeV for the final two weeks of running, during which luminosities approaching 3.0 x 10°! cm? s!

were again achieved. These high performance levels were due mostly to very small vertical beam sizes,

leading to values of the beam-beam parameter up to 0.05. For the final run of the year, the current restrictions

were relaxed and almost 6 mA, in four trains of two bunches per beam, was successfully put into physics. A

record peak luminosity of 3.4 x 103! cm”? s! was recorded by one of the experiments. Efficiency for physics

was dramatically lower than during Z° running, with around 70% of coasts lost on account of RF problems.

The overall statistics for the whole of 1995 are shown in Table 1, with data from previous years for

comparison. The significant drop in overall efficiency for physics comes from the high-energy period, as does

the increase in fills lost. The marked difference between peak and average intensities reflects the various

modes of running used throughout the year.

SPS + LEP Division

uols

ialg

AT

I + Sd

S

Table 1: Comparison of LEP performances 1989-1995

1989 1990 1991 1992 1993 1994 1995

Total hours scheduled h 3107 3433 4002 4883 4228 4476 4176

Sched. hours for commissioning h 1284 0 0 501 264 271 212

Scheduled hours for setting-up h 48 240 243 509 221 163 209

Scheduled hours for MD h 454 689 997 935 709) 867 685

Scheduled hours for physics? h 1321 2504 2762 3439 2943 3175 3070

Beam in coast h 469 1048 1242 1742 1619 1871 1414

Efficiency % 35 43 45 5] 55[61]P 59[62]°) 46[51]°

Peak | Avg. | Peak | Avg. | Peak | Avg. | Peak | Avg. | Peak | Avg. | Peak | Avg. | Peak | Avg.

Max. current at injection mA 285 | 22 42 3.1 4.3 3.5 5.7 4.7 5.8 4.8 6.4 5.2 8.6 5.1

Collision intensity mA 2.64 | 1.66'| 3.6 2.5 3.7 2.8 5 42 5.5 4.4 5.5 4.8 8.2 4.5

Initial luminosity cm? s!® 100 | 425 | 159 | ı1 51 | 10 11 15.5 | 145 | 224 | 123 | 249 | 10.6

Best luminosity cm”? s1® 1030 19 23.1 34.1

Integrated luminosity pb’! 1.74 7.69 17.39 28.6 40 64.5 46.1

Beta at the experiments (v) cm 7 43/1 &5 4.3/1.5 &5 5&7 5 5

Turn round time h 0:50 | 7:35 | 1:20 | 6:57 | 01:20 | 03:07 | 00:50 | 02:17 | 00:54 | 02:26 02:28 02:17

Mean coast duration h 12:45 | 5:00 | 22:35 | 7:30 | 27:00 | 08:00 | 26:30 | 08:35 09:40 09:30 09:30

Total number of coasts 97 143 154 199 168 197 194

Lost coasts % 35 33 36 36 37 23 37 2) (+91 h) Critical days.

Physics hours = filling+coasts+filling without coast+down-time+access+calibration.

[ ] with calibration.

d) Values from experiments.

The integrated luminosity accumulated at different beam energies in 1995 is shown in Fig. 1.

20000

18000

16000

14000

12000

10000

(nb-1)

8000

6000

4000 3122 3103

2000 44.67 45.59 46.44 65 68 70

(GeV)

Fig. I: Integrated luminosity versus energy for 1995.

SPS Fixed-Target Operations

Overview

From April to mid-October the SPS accelerated protons from 14 GeV/c to 450 GeV/c, interleaved with

leptons from 3.5 GeV/c to 20 GeV/c on two out of the four cycles available. The other two cycles were

replaced by a Machine Development (MD) cycle consisting of an injection plateau adjustable between

12.9 GeV/c and 14 GeV/c. After the technical stop in October operation changed to lead-ion acceleration from

5.1 GeV/c/n to 157.8 GeV/c/n. At the same time the top energy for leptons was increased from 20 GeV to

22 GeV. Five long periods were available for dedicated MD studies as well as several short “Wednesday’

proton MD periods.

The Proton Run

Operation with protons was carried out with a super-cycle in which the main 450 GeV proton cycle was

followed by at least two 1.2 s duration lepton cycles. From August onward, a 1.2 s duration proton MD cycle

was included in the super-cycle. This was used for preparing the lead run. The use of two proton cycles inside

the same super-cycle was a first for the SPS. With the main proton cycle a new record peak intensity was

established: 4.2 x 10°! protons were accelerated to 450 GeV in one single cycle. A total of 1.95 x 101? protons

were delivered on all targets, with 1.2 x 10!? protons delivered to the T9 target alone. This target serves the

two neutrino experiments CHORUS and NOMAD. The average intensity per pulse was 3.4 x 103 protons.

The overall efficiency of the SPS for delivering a proton beam was 77%.

SPS + LEP Division

The SPS machine was started up with a new access system. The access system assures personnel safety by

preventing or regulating personnel access in the machine depending on the state of the equipment or the

presence of beam. A very careful and concerted approach was needed to recommission the machine with the

new system. Despite the usual small technical problems, and increased time delays when accessing the tunnel,

it was possible to start the machine up in two weeks without any safety problems. The new access system will

ultimately allow the operators to have a more complete picture of the state of all the equipment from a safety

point of view.

The availability and quality of the beams provided by the CPS was remarkable taking into account the

complete re-wiring which was performed on the booster and PS RF systems. After the two-week setting up

period the Easter weekend was spent with smooth running for physics at moderate intensities. The week after

Easter was used for slowly raising the intensity and conditioning of the RF cavities and extraction septa. At the

same time the neutrino production target T9 and the beam were re-aligned with respect to the neutrino beam

line and experiments. This alignment yielded an increase of neutrino flux of 5% and a better centring of the

beam in the experiments. The installation of an additional beam current monitor in the proton beam line

towards the neutrino target allowed a more precise minimization of the beam losses and thus a better control of

this very intense beam throughout the year. After two weeks of physics running 3.5 X 10" protons per pulse

could be reliably accelerated.

During 1994 two major problems marred the operation of the proton beams in the SPS: the new control

system’s reliability and the sensitivity to the longitudinal beam distribution of the superconducting RF cavities

that are used for the lepton acceleration. The work performed during 1994 and the 1994/95 shutdown was

clearly beneficial. Both problems were virtually non-existent in 1995. During the proton run very high

intensities were delivered to the neutrino experiments. At the end of the run an average intensity of

1.86 x 10" protons per pulse was delivered to the T'9 target.

The very high intensity proton beam induces a higher remanent radioactivity. This is due to the

unavoidable beam losses in the ring during each cycle. Before personnel access can be allowed, a longer

radioactivity cool-down time is thus needed. This is a well-known effect, and is the price to be paid for very

high intensity proton operation. In 1995 two breakdowns resulted in two weekK-long waiting periods before the

repair could take place. Both breakdowns were vacuum problems. A high-voltage vacuum feedthrough on an

electrostatic septum broke, causing a five-day stop of extraction to the West Area, followed by two days of

repair. A vacuum problem in a North external beam line caused this beam line to be off for five days.

During 1995 special attention was paid to the minimization of the beam losses in the machine. Firstly the

beam transfer between the CPS and the SPS was carefully monitored and optimized, in a common effort by

the crews of the two machines. The injection losses into the SPS were consequently reduced by a factor 2.

Secondly, during the acceleration cycle and the extraction, careful optimization of the machine parameters

resulted in relatively lower losses than in previous years.

The Lead Run

b32*+ ions were injected with an energy of 5.1 GeV The lead operation was carried out with a cycle where P

per nucleon and then accelerated to an energy of 157.7 GeV per nucleon. The simple acceleration scheme used

for protons is not possible for lead. The RF cavities have a too-narrow frequency bandwidth to deal with the

SPS + LEP Division

change in revolution frequency between the two extreme energies for such heavy objects. A different scheme,

using fixed-frequency acceleration, was thus employed. In this scheme four batches, each 2 us long, circulate

in the machine. The inconvenience of this scheme is that at extraction the duty cycle is reduced to 31%. This

penalizes the experiments’ data-taking capacities. In 1995 an intermediate flat top at 10.2 GeV per nucleon

was inserted into the cycle. At this energy the classical RF becomes usable for Pb$2* ions again. The beam was

accelerated with the fixed-frequency system up to this energy. On this intermediate flat top the beam was

debunched and then re-captured by the classical RF where all RF buckets are filled. Acceleration to the

extraction energy then proceeds as for all other beams. The result of these RF manipulations was an increase

in duty cycle from 31% to 84%. The average number of charge accelerated was 2.4 x 10! charges per pulse.

The peak intensity achieved during the 1995 run was 3.9 x 1019 charges per pulse. In total 1.52 x 101? charges

were delivered to the experiments during the run. This is a factor 2 increase with respect to the 1994 run.

During the lead run the machine had an efficiency of 86%.

In 1995 a significant part of the setting up work for the lead run could be done during the proton run using

the second proton machine development cycle. In particular all problems related to the CPS-SPS transfer of

the ions could be studied well in advance of the run.

Lepton Cycles

During the operation of the lepton cycles in 1995 advantage was taken of the progress made during 1994.

The use of the two-batch (2 x 4 bunches) scheme for leptons, proven in 1994, liberated time in the super-cycle

for one proton development cycle and one lepton development cycle. This spare lepton cycle was used to

consolidate the move to an injection energy into LEP of 22 GeV. During the last part of the LEP run, the so-

called LEP 1.4, all lepton cycles were operated at 22 GeV. No adverse effects of this higher energy were

observed in the SPS. The electrostatic septa did not display any increase in spark rate. Overall when LEP was

requesting beam the SPS was able to deliver 80% of the time.

Conclusions

During 1995 the SPS achieved record performances with both protons and lead ions. The efficiency, peak

intensity, total intensity, and duty cycle were all up to very encouraging levels. In parallel to this performance,

the machine moved further towards true multi-cycling. Given multi-cycling one will be able to develop the

cycles and beams for future operation during standard physics conditions.

Power Converters

SPS

The smooth running of the SPS power converters was the major pre-occupation of the group for this year.

To this end considerable effort was given to the maintenance and verification of performance during the

shutdown. New facilities were installed to enable easy verification of the calibration of the mugefs. These

facilities have helped to maintain the performance of the mugefs throughout the year.

SPS + LEP Division

Although the reliability of the SPS auxiliary power converters was better than last year, they still have a

rather high fault rate and an improvement programme is under way. Although this is making encouraging

progress, much effort is still required.

A prototype of the nugef (an upgraded mugef) was installed in the machine and gave good results. The

design of anew ramp card is well advanced. A prototype of the new regulation and control interlocks is almost

ready. New closed-orbit dipole power converters were produced by industry and will be installed during the

shutdown.

The converters in the Experimental Areas continue to give high fault rates, but, as mentioned last year, no

resources are available to study or implement an upgrade programme. In the meantime an essential

maintenance programme is being carried out during the shutdown to try to prevent the fault rate increasing any

further. One of the major sources of breakdowns was the polarity reversal switches and a modification has

been developed and will be installed during the shutdown.

The power converters for Vertex (NA49) were installed and commissioned and modifications were carried

out on the ATLAS power converter.

LEP

The LEP power converters are now all calibrated so that their maximum output current corresponds to the

maximum energy requirement and where necessary the converters were changed to allow this. The reliability

of the power converters was similar to last year and as such remains very good. The last of the transformers

(built by a Russian manufacturer) for Phase II of LEP were repaired and installed. All klystron power

converters are now operational. The RF tuning power converters for Phase II were built by industry and

delivered to CERN. Orders for the extra klystron, RF tuning and ion pump power converters for Phase IV are

being prepared.

The spare ALEPH power converter was commissioned and the transformer for the OPAL power converter

was repaired.

Operations

Studies and preparations were carried out during the year for the move of the Control Room for the North

Area (CRN) to the Prevessin Control Room (PCR). The move will take place during the shutdown. It is from

here that the operators provide assistance to the physicists and carry out their first line intervention on the

power converters.

LHC

Studies and development work for the LHC, as well as operation and modifications on the test stands,

continue. The CELL power converter was modified and tested and is being installed in Block 4 for short

sample and cold diode testing.

SPS + LEP Division

Development work is under way on new high-precision references, ADCs, and, with the help of industry,

high-current DCCTs. These are all necessary for the high-performance requirements of the LHC.

An upgrade of our high-precision calibration laboratory is also in progress to enable the verification of the

performance of these devices. This includes the installation of the 20 kA range extender and the high current

calibrator. The latter was manufactured in Canada and successfully tested in the Canadian Standards Institute.

The facility should enable us to calibrate 20 KA output DCCTs to the part per million level, reproducing the

required working conditions of the LHC.

New digital control loop techniques for controlling the power converters using predictive and adaptive

algorithms were studied. The results indicate that the performance can be improved to the part per million

level for both static and dynamic parameters.

The group also made significant contributions to several of the working groups studying the LHC,

including the Electrical Powering and Cost Optimization group. The chapter in the Yellow Book devoted to

powering and power converters is a result of some of this work.

Most of the power converters will be installed underground and will be competing for space with other

equipment. Collaborations with industry to develop switch-mode power converter modules which greatly

reduce the volume requirements for a given power output have received much attention. Contracts were placed

with industry for the development of 4 kA/6 V modules. These will be used, in parallel configurations up to

20 KA, on new LHC test stands, in our standards laboratory to evaluate DCCTs and for compatibility tests on

the control electronics. |

Towards the end of the year the Dynamic Effects Working Group was formed, one of the aims of which

was to better specify the performance requirements of the power converters. Encouraging progress was made.

Radio Frequency

SPS

Proton Operation

As is the case every year, much effort went into maintenance work to ensure the reliable operation of the

SPS RF power plants. These plants consist of several types of cavity and about 140 tetrode power amplifiers.

Also included in the maintenance effort is auxiliary equipment, such as the high-voltage power converters,

regulated power supplies, air and water cooling systems, interlocks and controls.

Major improvements were made on the 350 MHz power plant for the superconducting (SC) cavities which

are used for lepton acceleration in the SPS. All final amplifiers are now equipped with a new version of higher-

order mode suppressor and a new anode overcurrent interlock system which permits overloading of the power

tetrodes for short periods of time without damage.

SPS + LEP Division

The 352 MHz SC bi-module with fixed couplers was replaced by one with variable couplers. Both

installed bi-modules now have variable couplers allowing strong passive damping in the event of an amplifier

or cryogenic breakdown. Modifications to the low-level power systems were incorporated to improve the

robustness of the system. These, and the attention to beam structure quality, which strongly affects the power

demanded at revolution frequency harmonics from the amplifiers, have considerably improved the system

reliability. Two further changes to extend the capabilities of the system were tested during the year. Firstly by

taking advantage of the variable couplers, the coupling on one cavity was increased by 5%. This increases the

current compensation capability of the cavities at the expense of slightly lower accelerating voltage for

leptons. During the next shutdown an additional increase of 10% will be applied to all four cavities. Secondiy

a new filter that rejects revolution frequency components while allowing gain at the synchrotron frequency

sidebands was placed in the feedback loop of one cavity. This in principle allows increased impedance

reduction in the cavity and hence more beam stability while reducing the power demand from the amplifier.

First tests are promising and will be continued next year.

One set of two transverse dampers was modified to run with lower power dissipation, and was used

continuously this year with no problems to damp the high-intensity proton beam. Following this success the

other set of two will be modified during the shutdown. Initial tests on pick-up sensitivities have shown that it

should be possible to use the dampers with the ion beam to optimize the injection steering. To this end new

electronics are under development.

Lepton Operation

LEP now operates with four bunch trains symmetrically positioned in the ring. To fill the four positions

from eight bunches in the SPS the leptons are now accelerated in the SPS in two sets of four bunches placed

asymmetrically around the ring. This is possible owing to a change of harmonic number in the 100 MHz and

200 MHz RF systems. Four of the six 100 MHz standing-wave cavities were retuned by mechanical

deformation during the long shutdown. The 200 MHz cavites were retuned by a change in cooling water

temperature.

The 100 MHz system software was upgraded and extended. The system was included in the new LynxOS

based PCA and X-window based MMI control system. Work has started on the adaptation of the software for

the 200 MHz standing-wave system. A first step in the upgrade of the controls for the SC 352 MHz system for

lepton acceleration was completed. Standard interface equipment was installed to simplify maintenance and to

make additional remote control facilities available. New software for improved fault diagnostics and alarm

generation for the power system was also installed.

Ion Operation

The lead ions are accelerated in the SPS using fixed-frequency acceleration to accommodate the large

variation in particle velocity, this precludes the use of fixed harmonic techniques with the SPS travelling-wave

cavities. The extracted beam is strongly modulated at multiples of the revolution frequency due to the holes in

the beam structure that are necessary for the phase adjustment between batches. This structure seriously

decreases the effective spill time. This year a new cycle was introduced incorporating an intermediate flat top

at 26 GeV/c. Up to this energy the beam is accelerated as before, it is then debunched and, after an appropriate

SPS + LEP Division

delay, recaptured. During this process the beam becomes evenly distributed around the ring and also evenly

spread out in phase space. It is then accelerated at fixed harmonic number, the remaining frequency swing

being, by then, within the bandwidth of the cavities. The average spill duty factor is increased from 30% to

84%. Because of this there are high data-taking gains in the experiments due to the reduction in event pile-up.

The price to pay is a small loss of intensity at recapture, and a slight reduction in flat top length.

SPS as LHC Injector

The microwave instability threshold in the SPS was studied in machine development sessions by injecting

single bunches at 26 GeV/c with bunch lengths close to those foreseen for LHC beams. In parallel, theoretical

work enabled the analytical description of the bunch shape evolution when the bunch is injected into a

mismatched bucket in the presence of a broadband reactive impedance. Results suggest that the onset of the

instability is best defined by measurements made with RF off and that injection into a mismatched bucket

which is too large in dp/p gives better control in the injection transient phase. The analytical results of bunch

shape change in the case of RF off were used to measure the low-frequency part of the broadband impedance

of the SPS by anew method.

A 400 MHz SC cavity together with its power amplifier was installed in LSS4 to allow preliminary tests in

the SPS with high-intensity proton beams. Eventually three of these cavities will be installed and used to

compress the bunches prior to extraction towards the LHC.

The installation of this prototype 400 MHz SC cavity allowed the first tests to be made on the compression

techniques to be used to tailor the beam to the requirements of the LHC. The fixed-frequency techniques

developed for lead ions permit acceleration of the proton beam from 14 GeV/c to 450 GeV/c keeping the beam

spectrum outside the cavity resonance. The power demand for beam current compensation is then minimal. At

top energy the beam spectrum is moved down in frequency towards the cavity resonant frequency. The beam-

induced voltage in the ‘capacitative’ impedance then increases, focuses the bunch, and reduces the bunch

length.

The new cavity was kept cold for a period of several weeks during which a proton beam of 7 x 101? was

successfully accelerated at fixed frequency and used to induce 1 MV in the cavity at 450 GeV/c. These

promising tests will continue next year.

The injection of short (2 us) high-intensity batches at 14 GeV/c during machine development helped to

define the modifications necessary for the SPS damper. This work also aided the specification of the LHC

damper itself. Different modes of damping were investigated, aided by collaborators from Dubna, Russia. This

work will continue in 1996.

SPS + LEP Division

LEP

Superconducting RF System

During each of the two three-week technical stops in June/July and October, four new modules were

installed and the RF units concerned were brought into operation. In June two modules were added in

unit 673, which completed point 6 as foreseen in Phase II, and two modules were installed in unit 233. During

the October stop the complete RF unit 872 with two klystrons and four modules was installed at point 8. This

brought the total number of four-cavity modules in LEP to 16.

All the high-power klystrons and circulators initially ordered for LEP2 were delivered and tested at CERN.

A large fraction of the wave guides for LEP2 were also delivered. Adjudication for the procurement of

additional klystrons and circulators for the LEP2 Phase TV upgrade passed through the Finance Committee in

December. The low-power electronics for LEP2 Phase III was constructed. Construction has begun for

Phase IV.

Throughout the year work in the RF straight sections continued. Ninety per cent of the cabling work for

Phase II is finished and all racks for the RF controls are installed. All racks are pre-cabled at the surface and

whenever possible already equipped with the electronics crates before installation. The preparation of racks

for Phase III has started and is well advanced. In order to save commissioning time for newly installed

modules, the cabling and the electronics were debugged to a large extent beforehand using a computer-

controlled simulator.

Radiation detector systems to be installed at both ends of SC modules as diagnostic tools were developed

and tested. The order for series production was placed.

The optical fibre cables running from the surface buildings to the RF system in the tunnel were replaced by

a delay-compensated type. With this modification four complicated feedback systems were made superfluous.

Prototype microwave ferrite absorbers, integrated into pumping manifolds, were built. They are intended

to trap that part of the high-order-mode (HOM) spectrum of the modules that propagates into the beam tube.

Laboratory measurements indicated 90% absorption of incident microwave power, whereas initial beam tests

in LEP, using calorimetric methods, gave the first experimental evidence of HOM power radiated from the SC

modules into the beam tube.

The stand in SA2, used for conditioning power couplers at room temperature, became operational in 1995.

This stand uses a 800 KW klystron as an RF power source and a spare HT power supply as aDC power source.

Otherwise standard LEP equipment is used to complete the stand. This stand was used extensively during the

year for the conditioning of couplers.

Another stand used for conditioning and development of power couplers for the 1 GHz cavities of the

longitudinal feedback system in LEP was also put into operation in 1995. A third stand to be used for

conditioning of power couplers for the copper cavities is under construction.

SPS + LEP Division

LEP Operations

All the 120 copper cavities are still in place in LEP and are used routinely for LEP operation. With the

increasing number of installed SC cavities, some of the copper units have been switched off during operation

for physics in order to keep a certain balance of RF voltage around the LEP ring and to gain experience with

operating LEP with a maximum number of SC cavities. In general the performance of the copper RF system

was very satisfactory during 1995.

The klystrons for the copper RF system operated on average 4000 hours each in 1995 and a large number

of them are by now approaching a total of 30 000 operating hours. Out of the 16 klystrons installed for the

copper system one was replaced owing to a failure.

During the first part of the year with LEP running at 45 GeV the SC RF system was gradually brought into

operation within the limits of acceptable RF asymmetry around the ring.

A big effort went into studying the nature of the SC cavity field oscillations. These studies finally revealed

that the oscillations have two sources. One component comes from the cryogenic system, the other one, much

stronger, is an inherent instability which couples stored electromagnetic energy to movements of the cavity

walls at the mechanical resonance frequency of the cavities. This oscillation amplitude depends on the

detuning of the cavities and the square of the electric field. Several methods were tried to suppress these

oscillations. The one finally used consisted of partially compensating the beam-induced tuning offset. This

was successfully implemented on all installed cavities.

In order to improve beam stability at higher currents, an RF feedback system was developed using the

vector sum of the fields in all eight cavities connected to one klystron. This will eventually be used in every RF

unit. Prototypes were built and tested during operation of LEP.

Towards the end of the year the copper RF system at point 6 was switched off completely and only SC

units were used. Since during physics not all SC units could be used simultaneously at their nominal fields, all

units, in turn, were brought to 6 MV/m with beam currents of up to 7 mA during ‘beginning-of-fill MDs’.

Several times a unit was operated during stable physics coasts up to nominal fields without problems.

After the October stop LEP was operated at 65 GeV, later at 68 GeV, and briefly at 70 GeV. The operation

was, particularly at the beginning, plagued by teething troubles with the new units, which had been

commissioned very quickly. Many intermittent faults appeared, even a klystron had to be replaced. There were

consequently frequent RF trips. In spite of these, many successful physics coasts took place. Several units

worked without trips at 6 MV/m average gradient for many fills. The only unexpected phenomenon seen was

the transient change of beam loading due to an RF trip, which leads to a further reduction of the total voltage.

This will be cured in the future by the vector sum feedback. The total beam current was initially limited to

4 mA in order to achieve more stable operation and avoid violent transients. Later the current was raised to

6 mA in four trains of two bunches.

SPS + LEP Division

LEP Feedback Systems

In preparation for bunch train operation the bandwidth of the cavities of the longitudinal feedback system

was increased by a factor of 6. In order to partially compensate for the corresponding voltage loss the system

is now operated in pulsed mode. Bunch train operation also required important modifications of the control

electronics.

In the transverse feedback system, the kicker amplifiers were modified and the control electronics rebuilt in

preparation for bunch train operation. The result was reliable operation and the system was used extensively

during the year, both for accumulation and during physics.

LEP Controls

The remaining SC RF unit controls equipment was installed at points 2 and 6 and commissioned with the

new SC RF modules. At points 4 and 8, all equipment was installed and made ready for tests, thus completing

the installation for LEP Phases I and II. Most of the additional control equipment for Phases III and IV was

ordered during the year and some of this has already been delivered. An upgrade of the G64 cavity Equipment

Controller (EC) crates, of which there is one per SC cavity, was successfully implemented in one RF unit. This

consists of the replacement of the eight-bit CPU by a VME bus 68030 CPU module running multi-tasking

software providing improved performance, increased functionality, and better local communications

reliability. Modification of all SC unit cavity ECs was started at the beginning of the end-of-year shutdown.

The RF Global Voltage Control (GVC) now replaces the original system of individual pre-programmed RF

unit function generators for the control of the total RF voltage during the ramp. A central GVC controller

continuously monitors the states of the RF units, sets the individual voltage level required, and increments

them gradually during the ramp. The system automatically compensates the loss of RF units due to trips and

maintains the RF distribution around the machine.

All existing RF control applications run from the PCR were moved from Apollo to HP-UX workstations

and some new graphics applications developed. Improved software facilities were introduced for the

‘mountain range’ bunch display, based on the use of a commercial instrument control package. A central

server for the source code of all VME RF unit ‘Data Managers’ was installed on an HP-UX machine. A re-

structuring and improvement of certain elements of software in the heavily loaded SC unit Data Managers was

studied with the aim of providing better communications reliability, more extensive alarm information, and

more flexible data logging facilities for 1996 running.

Superconducting Cavity Production

In 1995 reception tests of the industrial production of cavities and modules for LEP2 remained a priority.

Three European companies ANSALDO, CERCA, and ACCEL (formerly SIEMENS) continue to produce a

steady flow of cavities. Altogether 92 coatings were made in 1995 and more than 110 RF tests in vertical

cryostats. The overall result is that a total of 180 cavities were accepted by the end of 1995.

SPS + LEP Division

For LEP2 15 new modules were assembled in 1995 by industry and tested at SM18. Fourteen of these were

accepted immediately. This brings the total number of accepted industry modules to 39, representing

1560 MV accelerating voltage. The single module out of specification received in 1995 has already been

disassembled; the defective cavity will be rinsed at CERN.

The completion of the modules that are delivered by the firms without HOM or power couplers, or the

corresponding diagnostic instrumentation, has become an important activity. The couplers have to be mounted

on the module under class 100 clean-room conditions. This requires opening the module’s skin, adding

instrumentation and tuning the HOM couplers’ stop-filters. Tight quality control before closing the module is

necessary. Twenty-four modules have been made operational at CERN in this way. There has been a single

incident: a cavity had to be disassembled and rinsed at CERN; the module is now operational.

The helium-gas-cooled cables, used to transport HOM power inside the module insulation vacuum, were

replaced by a technically superior, much simpler and less expensive solution, using rigid coaxial lines. These

lines were tested up to 900 W on an operational unit with a 640 MHz power source, thus showing the technical

quality of this method. Parallel tests on connectors in vacuum showed the latent danger of the helium-gas-

cooled cables with connectors at higher power levels.

The cavities of the bulk niobium modules are rinsed and controlled before reassembling by AT-VA. The

first module is finished and the second under preparation. A solution for obtaining a safety level for the HOM

power transport in the bulk niobium modules is under development using special semi-rigid cables and an

additional feedthrough, the application of the coaxial line solution being prohibited by the different layout of

those modules.

Part of the two older test bunkers’ instrumentation at SM18 was changed for LEP ‘tunnel-standard’

equipment thus avoiding repair problems in case of failure.

More than 100 RF couplers have been built and most of them are already installed. It seems that a DC bias

of the antenna line is the best method for suppressing multipacting and reducing deconditioning. Several

versions of the high-voltage capacitors, which allow the bias voltage to be applied to the inner conductors of

the power couplers, were tested. The feasibility of cooling the inner conductor of power couplers with air

instead of cold helium gas was demonstrated. The design of the new HV capacitor has been based on that of

HV anode capacitors, developed for high-power tetrode amplifiers in the SPS. The new capacitors have passed

all high-power RF tests and have operated reliably in the LEP machine.

The addition of a second RF frequency to suppress multipacting in the power couplers was only partly

successful and delicate to use; the method was not pursued further.

The couplers have been tested under matched conditions up to 280 kW CW on a warm test cavity (limited

by overheating of this cavity) and up to 150kW CW on a SC test cavity (limited by the cavity field and

cryogenic power). After detuning of the cold cavity an equivalent power (i.e. the travelling-wave power

producing the same field as the peak field) on the coupler line of more than 250 kW could be applied. The

high-power tests will continue in order to find the power limits of the present coupler.

SPS + LEP Division

Even though DC bias is used for LEP operation to suppress multipacting and deconditioning, the couplers

should be conditioned up to full power on the cold cavities, without DC bias, to permit safe operation.

Conditioning tests on a liquid-nitrogen test bench have shown that gas condensation on cold surfaces is a

major source of multipacting. It was also found that the warm ceramic window after exposure to air during the

mounting operations is the main source of gas. Since the ceramic window part of the coupler protrudes from

the cryostat, it is relatively simple to perform in situ bake-out of this part before the cool-down of the cavity.

By using this procedure it was possible to reduce the conditioning time to reach full power on the cold cavity

by about an order of magnitude.

The installation in hall 180, known as ‘the test string’, was running routinely. This allows the final testing

of finished modules to be done before their installation in LEP. This testing is done at a temperature of 4.5 K,

with a klystron as RF power source, up to the design gradient of 6 MV/m. Normally two four-cavity modules

are run simultaneously, fed in parallel by one klystron. The time required per test is three weeks on average,

including installation, cool-down and warming up. In total 18 modules and one single cavity were tested. The

test string was also used to check the reliability of components and procedures.

Superconducting Cavities R&D Programme

The physics of the niobium layer is being studied with emphasis on impurities and grain size. A cavity was

designed and commissioned in which the impurities present in the superficial copper layer could be measured.

As a result the hypothesis of impurity trapping in the niobium from the copper substrate is excluded.

The frequency dependence of the RF losses was studied in a 500 MHz cavity by exciting it in several

modes. Linear dependence is the most appropriate conclusion.

The observation of an optimum temperature during the coating of the LEP2 cavities was confirmed by the

testing of several 1500 MHz cavities coated at different temperatures at Saclay.

The 1500 MHz cavity programme launched some years ago produced its first conclusions. The study

aimed at the understanding the slope of O(E). Evidence is increasing that magnetic flux penetration into the

surface, or equivalently a transition from the SC into the normal conducting state in synchronism with the

magnetic RF field, may play a role. An interdivisional programme has been launched in an attempt to

understand the parameters governing the slope of O(E). The main topics addressed were the dependence of the

slope on the layer thickness and on the static magnetic field. Results are comparable to those obtained before

with the cavities coated at Saclay. At the same time more efficient use was made of the already existing

facilities for production, chemical processing, and final treatment of series of 1500 MHz copper cavities.

Three of these cavities were post-annealed with a laser gun in order to modify the grain structure. Up till now

this treatment has given poorer results.

A ‘triaxial cavity’ is being commissioned, which should allow the assessment of the slope of the O(E)

curve on samples, the metallurgy of which can be analysed after dismounting. This cavity is based on a design

from CEBAR, and to accomplish its purpose must allow for about twice the RF field obtained at CEBAF.

Therefore six triaxial cavities (four made of copper with lead plating, two made of bulk niobium) have been

manufactured in parallel, in order to find the best solution. Preliminary results on the niobium one resulted in a

maximum field close to that obtained at CEBAF.

SPS + LEP Division

LHC

A major milestone in the design of the LHC RF system was the decision to use separate cavities for the two

beams and to locate the RF system in point 4, in a region of enlarged beam separation. This will allow a more

realistic design of the RF couplers and a larger safety margin at injection against uncontrolled beam losses.

The design of the mobile main couplers for the LHC SC cavities with a forward power of up to 150 kW,

i.e. an equivalent power of up to 600 kW, is practically finished. Construction of prototypes will start in the

coming year.

The prototype 400 MHz, 50 kW power amplifier has been installed in the SPS and tested successfully with

beam on the prototype SC cavity. The new ‘passive damping system’ for this cavity has been put into

operation in the SPS and worked perfectly, even at very high beam intensities.

Development work continued on the tuning system of the cavity since it has a strong influence on the

design of the cryostat and the layout of the eight cavities for each beam of the LHC. A cavity is tuned by

adjusting its length with a slow and a fast actuator located outside the cryostat at room temperature. The

actuator movements are translated to the cavity via a rigid structure that partially consists of carbon fibre in

order to avoid excessive heat loads. The slow actuator is a conventional screw-drive whereas the fast actuator

uses giant magnetostrictive material which has only been made available recently in the required dimensions.

In collaboration with the University of Lund (Sweden) a prototype fast actuator has been developed. It will be

evaluated during the coming year and also used for fatigue measurements of the carbon fibre element.

Development of higher-order mode couplers for the LHC has continued. A model of the tuned-antenna

coupler for the non-propagating dipole modes has been built. Damping of the propagating modes in the beam

tubes by wideband antennas is being investigated further.

Following the decision to use separate RF systems for the two LHC beams, the longitudinal feedback

cavity has been redesigned taking into account the new beam dynamics’ requirements and the increased

physical separation between the two beams. The result is a design with higher R/Q to reduce the power

requirement, and larger separation between the required operational frequency bandwidth and the first higher

order mode. Next year the construction of a prototype cavity will be started.

SPS + LEP Division

Technical Support Division

In the course of 1995 a number of projects covering various technical areas were completed. A spectacular

event was the commissioning of the new heating plant of 45 MW installed capacity during the last beautiful

autumn days of an extended mild season. The installation was ready to heat the laboratory of the Meyrin site

before a cold wave hit the area.

In late autumn the rebuilt SC, financed by a generous gift from the Canton of Geneva, was handed over to

the physics user community and very soon all offices and laboratories were fully occupied. CERN also

inaugurated the new hostel which was built within the forecast time and budget and, as can be judged by the

high occupancy rate, satisfies a long-standing need.

The process of selection of the engineering offices involved in the LHC civil engineering design and

supervision works made excellent progress and final proposals were readied for presentation in early 1996 for

approval by Finance Committee.

Much time and effort was invested in the preparation of new calls for tenders covering very diverse

technical areas and kinds of work: maintenance of electrical system; maintenance of cooling and ventilation

systems; cleaning and maintenance of the laboratory, hall and office space throughout the laboratory, just to

name the biggest and most complex tasks. It is appropriate to acknowledge the active help and participation of

Finance Division and the Legal Department. In this context it also turned out to be of great value to seek

advice from legal offices in the Member States. The learning process is not yet complete and further effort will

be needed to consolidate the now existing methods and procedures for the preparation of the documents for

calls for tenders and the selection of competent firms.

Considerable time, effort, and imagination were invested during the second half of the year to prepare the

merging of the two Cooling and Ventilation Groups which still existed in CERN. By the end of the year all

parameters covering this very diverse and technically rich field had been cast into a new organizational form

which almost immediately yielded substantial savings in staff and space requirements.

A second restructuring effort concerned the rationalization and improvement of the maintenance and

operation effort devoted to the civil engineering surface structures and the associated technical equipment. At

the same time there was a strong wish to reduce the tasks of the Civil Engineering Group by removing the

more conventional tasks so as to free resources for the fast growing commitment to the civil engineering

problems of the LHC. The final result was the creation of a new Group to become operational in January 1996

and whose budget and staff were carved out of the existing groups in the Division.


This regrouping of activities and streamlining of procedures put a heavy strain on many colleagues and

made great demands on their professional and human flexibility. It is most appropriate to acknowledge this

global effort here.

The Division is thus set to face the work load of the coming year in a determined and positive spirit.

Civil Engineering

The work on the new hostel (Building 39), including the surrounding area, was completed in April and the

hostel began receiving its first guests in May 1995.

The external finishing work (facings, windows, etc.) of the physicists’ building (Building 40) were all

completed according to plan. The interior works are proceeding normally. The design studies for the

surrounding area (roundabout, car park, grounds, lighting) were made and the work is to be carried out from

February to May 1996.

The fitting-out of an office complex in the former SC area was completed on schedule and the offices were

occupied in stages from May to July 1995. The redevelopment of the surrounding area, completed in

October 1995, created a large number of additional parking spaces.

Refitting work on the central library began at the end of the year.

Other important work under examination includes:

— the extension of the ISOLDE experimental hall,

— the construction of a student hostel to replace the existing barracks.

Concerning the LHC design studies, three calls for tenders corresponding to the three geographical areas

into which the project is divided (point 1, point 5 and other points) were issued for the design and supervision

of the whole operation. A start was made on examining tenders for two of the areas in December with the

assistance of outside experts, in accordance with a new CERN procedure (technical and commercial sections

examined consecutively).

The geotechnical surveys were performed satisfactorily and to schedule. They caused a number of aspects

of the project to be revised, particularly in the case of the TI2 injection tunnel. They will allow precise and

complete work specifications to be drawn up, which is the best possible guarantee against the risks of

subsequent claims.

The design of the structures continued to be fine-tuned throughout the year, in conjunction with the various

CERN and outside parties (architects, experts) involved.


SEEN

FIT

3% ES ee

ee En BE

PRGPIT

IR 14


LHO - ATLAS CAVERN - UXA 15 - POINT 1 . LEP GAVERN - UX - POINTS 4-68

u ON 1


areas under

sence ol an

auion ol cooling lowers so Ihal Ihe water runs in a hat used drinking water and was discharging tdi

into Ihe river,

A major project was undertaken in 1995 to reduce the consumption of drinking water and, at the same

time, to overhaul old equipment and implement automation and remote control of the system: the Main

Magnet cooling station. This alteration implies that the operating temperature regime of the PS magnet will be

higher and has been approved after six months of tests.

The investment required is of the order of 700 kCHF.

DI Group

The group covers the following two areas of activity:

— management and organization for the whole of the Division;

— site maintenance (cleaning, grounds, technical support for the restaurants).

Management and Organization

(Activities in support of the Division and Group Leaders)

Considerable effort was made in the areas of analyses, interviews, proposals, and, finally, the creation of a

new group in ST Division bringing together all activities (until then carried out by CE, CV and IE groups)

linked to property management, in particular work on the site and buildings.

The aims of this new group (Technical Facilities Management) are to reinforce the quality of the work for

the divisions, reduce costs, and introduce a more global and consolidated approach to the industrial support

associated with these activities. ST Division’s existing technical groups will thus be freed from work not

connected with the accelerators and will be able to focus their efforts on the design and implementation of

large-scale projects.

Likewise, assistance was required in preparing and implementing the fusion of AT-CV and ST-CV groups,

in particular with regard to budget and personnel transfers.

The coordination of market surveys and calls for tenders for the renewal of industrial service contracts also

represented a considerable effort for the service. (N.B. ST Division manages over 40 contracts, amounting to

half of all CERN’s contracts in the industrial support field.)

Much time and effort was also invested in the core activities in 1995: budget forecasting and monitoring,

personnel management and administration, training programmes, trends and projections taking account of

departures and recruitment choices.


Site Maintenance Section

The call for tenders for the renewal of the hygiene and maintenance contracts was successfully completed.

An interesting representation of Member State bidders was achieved, among which were some of the largest

companies in Europe. (The return of the tenders was scheduled for 16 January 1996.)

Several of these firms expressed an interest and the Service was congratulated on the quality and new

approach of the specification’s contents.

To ensure that the technical management and supervision of the work of future work contracts are properly

prepared, a training programme has been set up in the Hygiene and Maintenance Service with a view to

introducing a quality assurance plan (model ISO 9002).

The market survey concerning the upkeep of the grounds and road maintenance was prepared at the end of

the year. The new contract is also being drawn up on the work contract model.

Design studies were made and implemented for the planting of several areas: the hostel building, the SC

area, the redevelopment of Route Gregory, etc.

With regard to Restaurant No. 2 in particular, the Service worked on a project to modernize the washing-up

area and refit and enlarge two lounges. In addition, it participated in the design study and construction of a

free-flow system replacing the special menu queue. The project is financed by the franchise-holder.

Heavy Handling and Transport, Car and Utility Vehicle Fleet, Maintenance of Hoisting and Miscellaneous Equipment

Heavy Handling/Transport Section

Handling

The activities of the Handling Section in 1995 covered mainly:

assistance during the scheduled machine shutdowns;

— assembling and dismantling of superconducting cavity modules at LEP and in Hall SMI8, including

the preparatory work;

— preparation of the LHC Section in SM18;

—- preparation of the beams for:

the North Area experiments (NA44, 48, 49 and 50),

the West Area (WA91 and 98),

DELPHI,

the PS Area,

the LHC experiments (ATLAS and CMS);


— removal/refitting activities for:

Hall 181 (installation of the press),

Hall 276,

SC,

Buildings 102 and 39.

Transport

People and equipment are regularly transported round the CERN site in various ways. ‘Long distance’

transport is also provided on request.

To this must be added the transport of equipment for CERN’s exhibitions in Cracow (PL) and SITEF in

Toulouse (F).

Various removal operations were also conducted according to divisional requirements.

Car and Utility Vehicle Fleet

CERN’s light vehicle fleet, which operates on the principle of annual or temporary hire to the divisions,

comprises 640 cars belonging to the Organization.

This fleet is renewed and maintained according to the programme agreed upon by the CERN Vehicle Fleet

Users’ Committee.

With regard to purchases of duty-free vehicles meeting users’ requirements there has been:

— an increase in orders to Spain;

—- areduction in the average age of the light vehicle fleet, which has fallen from 5.37 (at the beginning of

January 1991) to 3.00 (October 1995);

— areduction in the number of light vehicles purchased before 1991:

1991 = 476 1995 = 138

Hoisting and Miscellaneous Equipment Maintenance Section

The main activities of the Hoisting Equipment Maintenance Section for 1995 are summarized below.

Section Staff

The Section employs seven technicians (a new technician was recruited on 1 March 1995).


Equipment Concerned

The equipment comprises 2501 hoisting and handling items divided into 18 main groups, plus 92 lifts.

Contract Management

Main Contract (E042)

Maintenance of 2501 various items of hoisting and handling equipment.

The programmed preventive maintenance schedule covered 981 items.

Six Lift Maintenance Contracts

The statutory preventive maintenance inspections of the 92 lifts made by the lift manufacturers or

maintenance firms were carried out in accordance with the contracts concluded.

The 1000 preventive inspections, to which must be added 245 emergency or routine repairs, were made in

accordance with the safety regulations in force in the two Host States.

Renovation of Installations

Lifts

Three lifts were replaced.

Overhead Travelling Cranes

The work involved the drawing-up of specifications, calls for tenders and commissioning operations for:

replacement of a 10 ton overhead travelling crane;

— installation of 3 radio controls;

— installation of a 4 ton overhead travelling crane in the PS Ring (in progress);

— installation of a 1 ton underhung crane;

— installation of 15 power supply units (in progress);

replacement of the Central Stores crane (in progress).

Motor-Driven Doors

Four motor-driven doors were replaced. Dimensions (LXH in mm): 6250 x 6100, 5000 x 3900,

5950 x 5500, 4580 x 3300.


Electric Vehicles

Approximately 40 electric vehicles were completely overhauled.

Specifications were drawn up and calls for tenders sent out for the supply and fitting of new battery

chargers for the SPS vehicles with remote data transfer (in progress).

Work Requests

The Section dealt with 81 work requests (replacement of traction batteries, modification of the electric

cables of the passenger monorail in the tunnel, etc.).

Spare-Parts Management

The end-of-year stock-taking showed 3500 item references.

Such a stock is the result of the variety of makes and the obsolescence of the installations. In many cases

the manufacturer no longer exists and/or no longer makes spare parts.

Movements of items recorded during 1995:

— number of items received: 3573

— number of items issued: 3367.

Electrical Installations

The Service’s work was mainly centred on renovation projects on the oldest parts of the system (30 to

40 years) which will have to continue to be used for LHC. These projects, which were started two years ago,

will be completed in the year 2000 before the large-scale LHC construction work begins. Having lost its

central role to the Jura substation, the Sal&ve substation, gateway to CERN at the time of its creation, was

completely dismantled and replaced by a simple ring main unit, inexpensive both in terms of purchase price

and maintenance costs. The main PS substation, dating back to the same period, was entirely renovated. The

high and low voltage parts needed were no longer available on the market and were replaced by modern

equipment with computerized integrated control. The project to install a third 100 MVAR compensator at the

SPS to enable the two existing compensators to be renovated over a two-year period began with the

construction of two additional 66 kV sections and the installation of a new 18 kV substation supplying the

general services of the SPS and freeing the second 400 kV/18 kV section of the terminal station where the

third compensator will be connected. The ultimate goal of this project is to ensure the pulsed operation of the

SPS at 450 GeV, whatever the conditions, as injector for the LHC.

These projects placed considerable demands on the network operation service. The network operation

continued to be marked by a series of minor incidents due to the obsolescence of several of the supply,

distribution, control and protection systems. There was no serious breakdown this year.


The engineering service also played a major role in these projects. In addition, it contributed to the projects

of other services concerning the extension and renovation of buildings, support for experiments (NA48,

ISOLDE) and accelerators (renovation of the Prevessin Control Room, replacement of 100 km of irradiated

cables in the straight injection sections of the SPS, wiring of the new RF cavities for LEP). A four-year project

with the aim of removing 400 km of spent cables in the PS was launched to make room for the modernization

of the machine for LHC. This project provided an opportunity for CAD drawings of the PS structures and

cable routings to be made, thus providing computerized information that will enable renovation projects to be

carried out using modern management methods requiring few CERN personnel.

These projects left the constantly decreasing staff little time to take the LHC design studies any further

than preliminary drafts and estimates. Nevertheless, research leading to a divisional report was carried out on

the feasibility of introducing high-intensity superconducting links between the converters and the LHC cold

connecting boxes. This project was finally abandoned in favour of installing the converters very close to the

cold boxes using conventional cables, which was considered to be less expensive and to present fewer

technical constraints.

The adjudication of an industrial support contract for the design studies, installation, and maintenance of

the electrical supply system, resulting from a call for tenders sent out two years earlier, gave rise to a number

of problems. On the recommendation of the Finance Committee, the management of the electrical Service is

negotiating a joint venture between the two consortia who came first and second in order to obtain more

favourable tariffs while at the same time ensuring continuity of service linked to familiarity with the system

and operating methods. These negotiations are close to completion.

Controls and Communications

General

The reduction in the Group’s staff has been further accelerated by normal and early retirements and

transfers to other divisions or services.

At the same time, in order to cope with its ever-increasing work load, the Group has pursued its policy of

industrial sub-contracting. Efforts in rationalizing methods and in quality assurance have continued to be

made.

In order to cope with the ageing of installations and with the long-term programme in mind (LHC), several

global projects started in 1994 in the fields of access control (machines), fire and gas protection systems, etc.

and telecommunications were continued.

Within the general framework of the renewal of the various maintenance contracts, the Group renewed the

contract for the safety installations (fire and gas detection, etc.), part of the access systems, and will continue

its efforts with the telecommunications contract (voice and video systems) which is scheduled to be renewed

in 1996.


Telecommunications (Telephone, Radio, Video)

Following new developments in telecommunications, a long-term strategy was implemented (introduction

of GSM, examination of the DECT systems, development of the PABX).

An initial pilot phase of introduction to GSM was set up with two basic stations and some 300 users. In the

light of the very positive results of this experiment, it was decided to continue the operation with a view to

replacing the paging system currently in use.

Several initiatives were taken with a view to the self-financing of this activity.

Safety Systems (Fire and Gas Detection, etc.)

This programme of equipment renewal and system uniformization and modernization, undertaken over

several years in cooperation with TIS, is continuing.

A study commissioned by SAPOCO was made to examine the fire detection situation.

A general contract for the replacement of the old systems was concluded with an engineering company.

Access Control

An overall programme for modernizing the access control systems of the machines and experimental areas

is in progress.

As part of this, the SPS access control system was updated.

Likewise, the renewal of the experimental area access control system in the East Area and ISOLDE at the

PS was completed with modernization and unification in mind.

The access control monitoring system in the West and North Areas is currently being renewed and

transferred to NCP. |

The extensive introduction of industrial methods and systems has been strongly encouraged in these

projects.

Technical Control Room (TCR)

It has been possible to keep all the existing overall monitoring applications and the remote control

environment in good working order, which has involved a great deal of effort. New applications have been

created, in particular for the electricity distribution and demineralized water production and distribution

systems for the PS and in the level-3 alarms system.


The examination of the problem of alarm transmission via the control system has been vigorously pursued.

The conclusion is that the only real solution is to introduce the data-server concept, which will allow other

improvements to be made at the same time. The examination was undertaken using the ‘'ESA’ method, and the

stages of defining requirements and manufacturing prototypes have been completed. The project will continue

in 1996 with the system’s industrialization and adjustment to the various control subsystems, for which a

working group involving several divisions has been set up.

The replacement of almost half the team of operators within a few months created a serious training and

efficiency problem. While the rotation policy required by the Management has unquestionable long-term

advantages, it nevertheless gives rise to not insignificant operating problems for the services.

The TCR handled 11 531 calls for assistance in 1995.


Finance Division

Introduction

The decision of the Council in December 1994 to approve the LHC project had important consequences on

the financial management of the Organization. The two major immediate consequences were non-indexation

for inflation of the contributions for the period 1995-1997, and the possibility of carrying forward budget

provisions for the LHC. The non-application of the cost variation index to the contributions obliged the

Management of the Organization to adopt an even more rigorous financial management than in previous years.

1995 was the second year in which the revised purchasing rules, approved by the Council in December

1993 (CERN/FC/3662-CERN/2006), were in full operation. After this second year, the results of application

of the revised purchasing rules showed a continuing trend towards more Member States reaching the industrial

return target of 0.8 for Supplies. On the Industrial Services side, it could take somewhat longer to reach the

target of 0.4.

As every year, important items have been the preparation of next year’s Budget as well as the Annual

Accounts. In addition, there was the work associated with the audit of the 1995 Annual Accounts by the

Norwegian Auditors with the corresponding reports to the Finance Committee and Council in preparation for

the June meetings.

Another area of activity was the preparation of two documents on the treatment of the contributions of a

new Member State at the end of its transition period, which resulted in the approval by the Finance Committee

of a new presentation of the scale of contributions.

Accounting Services

The Organization continues to observe the requirements of international accounting standards where they

are applicable, and has again made great efforts with regard to year-end procedures in order to adhere more

closely to the principles of accrual accounting and improve the disclosure and presentation of its financial

situation.

On 1 March 1995, new computer systems, known as HR (Human Resources) and AVCL (Advances and

Claims), were introduced for the management of personnel, payroll and other costs chargeable to the

Personnel Budget.

Finance Division

Implementation of the Budget

In view of continued budgetary restrictions, budget allocations were again confined to essential

expenditure levels within Personnel and Materials. In 1995, savings of some 35 MCHF for basic and

additional programmes were achieved. The additional programme concerning the construction of the new

building for physicists and the renovation of the SC building progressed during 1995.

Income and Expenditure

The following is a summary of income and expenditure in 1995

MCHEF

Income | 950.95

Contributions from Member States 910.46

Additional programme 20.35

Bank interest, GPM Project, compensatory income, etc. 18.53

Unused provisions + miscellaneous 1.61

Expenditure 915.97

[496.41 MCHEF for Personnel, 398.41 MCHF for Materials of the Basic Programme, and 21.15 MCHF for the

Additional Programme (18.35 + 2.80)].

Budget appropriations of 31.91 MCHF were carried forward to 1996 for the LHC Project, as provided for

in document CERN/FC/3839.

Additional income of 1.9 MCHF was transferred to the Special Reserve Account.

The closing balance amounted to 1.17 MCHEF.

Outstanding Contributions

As shown in the table below, contributions outstanding as at 31 December 1995 amounted to about

9.83 MCHEF.

Contributions outstanding as at 31 December 1995

Member States MCHF

Belgium 1.617

Germany 0.071

Greece 0.639

Portugal 5.157

Spain 2.346

TOTAL 9,830

All contributions outstanding were received in the first quarter of 1996.

Finance Division

Invoices

The number of invoices handled in 1995 amounted to more than 51 000 and bank guarantees to 480.

Cash Position

The cash position improved considerably in 1995 due to substantial payments of contributions by several

Member States during the first half of the year.

Despite the decrease in interest rates on the financial markets, income earned on these cash balances was

slightly higher than that budgeted for.

Pension Fund

In accordance with the Council’s decision, since 1st January 1992 the Pension Fund has paid all its

administrative operating expenses. In 1995 the total actual expenditure (Personnel and Materials) amounted to

2.3 MCHE.

Visiting Research Teams

During the 1995 financial year, 790 visiting teams had open accounts in our books. Some 4000 purchase

orders were issued to suppliers on behalf of the Teams. Furthermore, about 7700 invoices were made out for a

total of some 44.5 MCHF. These monthly invoices relate mainly to issues from stores, work done in the

workshops or outside, orders sent to suppliers, and miscellaneous expenditure.

LHC Collaborations

The necessary accounting and purchasing procedures to deal with the approved large LHC Collaborations

(ATLAS and CMS) were set up in the course of the year. In this connection, an important policy document

entitled ‘Financial Guidelines for LHC Collaborations’ (CERN/FC/3796) was presented to and approved by

the Finance Committee in 1995.

Purchasing Service

The introduction of the revised purchasing policy and procedures, as from 1 January 1994, resulted in a

significant improvement in the industrial return for a number of poorly balanced Member States.

The opportunity for firms from poorly balanced Member States to submit joint tenders together with those

from balanced Member States is a decisive change which allows a greater number of Member States to have a

Finance Division

share of important contracts. It has substantially improved the response of firms from non-Host States to calls

for tenders in the field of Industrial Services contracts.

The re-alignment procedure was used in 12 cases in 1995. It should be noted that all the requests for re-

alignment were accepted by the firms concerned. The average alignment factor is below 5%, although there

have been cases of re-alignment of up to 13%.

By the end of the year, 35 market surveys and 51 calls for tenders had been dispatched and the majority of

the resulting contracts placed.

The number of orders for the whole of 1995 totalled about 50 000.

The positive effect of the appointment of Industrial Liaison Officers was confirmed. It permits a continuous

improvement of the supplier database. The targeting of market surveys is more accurate and the number of

valid tenders is increasing.

In 1995, there were four national exhibitions. These were organized by France (4-6 April) comprising

46 firms, Germany (12-14 September) comprising 42 firms, the Netherlands (17-20 October) comprising

20 firms, and Poland (28 November-1 December) comprising 23 firms. Three national exhibitions are

planned for 1996 from the Czech Republic (11-14 June), the United Kingdom (8-10 October), and Italy

(19-22 November). Austria will organize a visit of firms to CERN (22-24 April 1996). So far, two Member

States have expressed their desire to organize exhibitions in 1997: Finland (February) and France (April).

In 1995, Finance Division organized technical presentations at CERN involving more than 50 Member State

firms.

Budget and Financial Planning

The Financial Planning and Budget Service prepared the Organization’s budget documents, the cost-

variation indices, and the scale of contributions, together with the necessary background information for

decisions by the Management. The service also contributed to the financial part of the Organization’s planning

documents. It was particularly involved in the financial part of medium- and. long-term manpower planning.

As far as the contributions of the Member States are concerned, the service prepared two documents on the

treatment of the contributions of a new Member State at the end of its transition period, resulting in the

approval by the Finance Committee of a new presentation of the scale of contributions.

Computing, Statistics, Purchasing and Accounting Databases

The Computing and Statistics Section is responsible for divisional hardware and software support, and for

the provision of-periodic (monthly, six-monthly, annual) or ad hoc management statistics at various levels

(divisions, management, Member State Delegations) concerning accounting or purchasing activities.

In close collaboration with the industrial liaison officers (ILOs) of the Member States, the Purchasing

Service and the Accounting Service, the Section is also in charge of the management of the CERN Purchasing

and Accounting Databases.

Finance Division

amjıpuadxa

Jo uonsnpaI

se's7zo I78-

|SE'STO Ir8-

0) payesogfe 3uIoau]

/

UONENIAIV

09°E09 9IF

S 09°E09

9IF S

SAL 'SIS

'SIDS

00'E87 66h

7 00'E87

66% 7

Juawasmqunas ga

91

01759 II

01'759 11

sodsey> Areuipioenxq

129

80'09€E Er

STHEl LP’ LSE

LO'SLO 9IE

zL’v91 6h’160

09€ Jusumms3yg

879

0L'8S6 ZL’6H7

IIT Ip'19p

BTE IE1ES6SO

I |88’I08

E6 FL’8OLSOTI

|I8’II0 006 7

suonestunuruo,) 979

06'559 7

PSOLI #9

18°60€ 6E1

ST’006 96

ES'LTS SS

8I’IST STE

1L'071 L89

Anendsoy JO

€579

05'8ET +

Er 707 09

VE’SBLIEST |ST869IISTE

IPL’TEO TOT

98'187 E19

S6 FOE ELOL

sosusdx> jeaen

Aynı] 7579

9 LIP Tr

o'0rr 786

PS'90S HSS

L6'E88 ISE

S8'6EL PS

00'8E0 ILET

s3s09 3ururei]

1579

L8'IP7 00'558

Iv’67Z €

07T SSz Zr7

sr 185 997

suonejal sıjqng

E79 s%J

pue

Or’ sI6 I 00'000

I v9 96H

9HLOI ITTH9r

ITS |06°779

6858 |TS’S69

676 EETSSESIS

JIOLELEFTIT |

susunked Ayred

prrys 779

15'678 885

VEIT SIHr VE

|6L’LSLOLTSE |TOZsı

9sT Ic

|ISIHISLHL |ILEPTIGEL

|TS’LBE 00r

EOI SSTAIOS

JELNSNPUL 179

SYUAIIJUOI

T7 177 0€

SY'LLL 96

6I’L8r #9

ES'VEE 8

YLIIS IIS

EP TEE 9IL

‘sseururss “embojjo)

S819

STH8l S6

LE'LOS OP7

88'178 drE

CH '601 6L5

9T’6ES ESS

SO'88I EIS

I Areigr]

9819

sg’E9 96 SIE

FI OT'L96

ZI ST’SOO

SOI SH LSL

ESLZILEGP |P0LITOLOS

sumrurad souemsuj

919

v66Ch 96T

IS |S0’E6S

OEI ELSEI6

vs IoL6zeE-

|rSE9 65'868

I IE'6IF

90L IS

spmg pue

Adısug 1909

0'865 865

09988 SI6EL

I|6L’EGF SET

IS |8Sr'886 996

9E |SL’T86

8LO 8F_

ISETIIG666 FE

|LSTHO ITOOL

98'056 86T

rI |rr’SSO

SLO rOZ

sasusdx4 3une1sdo

7

11’79E #ST

IT 09988

SIGL LOL’

SOLPSTES ITS

PZS HL6

TS |TO’EIO

691 IST

|LS'ISIHISEL |ETSIP

HSEEI |[869TT

LEI II

|EO6EE 195

6lr see

ER T jodpng

0L'667 L6S

87 0L'667

L65 8T

| TPuuossag

pszıenus) 179

00'SES 88E

gE'SLP TIL

L6YrTtrS 6

|61’E9L I6L

zs8gIo Ler

Il SSJEISOSSY

S649

9L’TIHO IL6

ISFIT6007_ |LI0TO

BIS FI

|P6'ESO EBI

8TISE TEL

6I smo]jaJ

9609

78°797 980

S8 |L9’69L

60€ LIT

|TL’SY6 ET

TEIL |LL'685

IT8 OP

|FG ESP ZBI

IT |76ITO

Hr9 9er

sIaquau JeIS

0619

85'098 Stt

98 |PS’6Sr

LEO ZLI

|9ETTITISE IST

|09’90L E6EOL

|r6ESP TEL

IT |T70'769

607 I6r

Puuosıaq I

IT ZIE FSI

IT |00'000

016 IE

09988 sı6L

|OL’soLrvsZTeEes |or'sse

0Tr GEL

|9S’TLP 007

ESE |E6°T9E

OL8 677

|EBYLI SPLES

|T6089 6LELZ

|SO'IEO 988

LP6 STVIOL

sqda ae

(IS ‘Sq

(HL ‘Idd

ri <

pıemIog

aurure1doig PIEeMIOT

9 uonsINgIV

Krug

SL

1S un)

Lv ‘IV

“II 'ND)

ae sa 20)

Aue)

pue umopyeaıg

[BuonIppY -A1IE)

sa

suolstalg suoISIAIG]

sımmpuadxq <SIs'sI9S

resruy>aL z07B10[590y

guuasay | FERSTUmpV|

SPeIOHard S66t

(sJuD4[ ssıms

u)

PADM1OYJ-KL1D) PuD

103995 Aq

aınnpuadx S66I

JO umopyvaug

Ivision Finance D

Personnel Division

Personnel Division deals with human resources management and administration concerning staff

members, fellows, associates, students and temporary labour, including aspects such as recruitment, job

classification, performance appraisal, advancement, salary administration, training and education, and

relations with the personnel. Members of the Division also participate in various committees and boards

related to these activities.

In 1995, the Division also devoted considerable effort to concluding the periodic review of the Staff Rules

and Regulations, and the five-yearly review of the remuneration conditions of the members of the personnel,

as described below.

Review of the Staff Rules & Regulations

This major review continued with discussions between the Management and the Staff Association in the

Standing Concertation Committee (SCC), and discussions with Member State delegations in the Tripartite

Employment Conditions Forum (TREF). Some outstanding issues related to the remuneration review were

concluded in a restricted tripartite group in December 1995. The 10th Edition of the Staff Rules and

Regulations, comprising various new features, was subsequently adopted by Council and the Finance

Committee respectively at their sessions in December 1995 for implementation on 1 January 1996.

Five-yearly Remuneration Review

Considerable effort was invested by Personnel Division in conducting this review based on remuneration

and related data collected by CERN from 17 national and international organizations or laboratories, and by

an external consultancy firm from high-technology industries in various Member States. After discussions in

the SCC and TREF throughout the year, and in a restricted tripartite group in December 1995, the review was

concluded by the Finance Committee and Council subject to further study of some topics in the course

of 1996.

Merit-Oriented Advancement Scheme ‘MOAS’

The annual advancement exercise was carried out under the conditions of the Merit-Oriented Advancement

Scheme. Annual interviews with written performance appraisals took place in the Divisions for staff at all

levels. An internal review of the scheme took place, resulting in some modifications to the pertinent provisions

of the Staff Rules and Regulations. A status report on the implementation of the scheme was presented to the

Finance Committee and will be discussed further in 1996 at TREF.

Personnel Division

Staff Recruitment

1995 was the first year of full operation of recruitment based on ‘staff complement’ numbers distributed

across the different sectors of the Organization. These numbers are reviewed as required by changes in the

work programme and structures of the Organization, as well as in the medium- and long-term plans.

A total of 98 newly-recruited staff members, selected from approximately 3500 applications received, took

up their appointments in 1995. One hundred and one selection boards were held with 813 candidates invited

for these interviews. The nationality distribution of the candidates invited and staff recruited is given below.

Table 1: Nationality of Staff Members & Fellows recruited in 1995

Staff Members Fellows

Country Candi dates Arrived App lica tions Selected invited received

Austria 17 1 10 3

Belgium 55 6 12 3

Czech Republic l — 7 _

Denmark 20 _ 2 1

Finland 13 2 9 1

France 139 18 65 7

Germany 114 21 104 15

Greece 6 2 26 4

Hungary 2 1 3 1 Italy 114 13 110 22

Netherlands 36 6 22 3

Norway 24 2 10 _

Poland 15 2 14 2

Portugal 21 3 9 1

Slovak Republic 2 1 11 _ Spain 58 3 59 3

Sweden 13 3 8 _

Switzerland 82 6 15 1 United Kingdom 80 8 61 9

Non-Member States 1 _ _ —

Total 813 98 557 76

Fellows, Associates, & Students

Some 2600 applications to the Fellows, Associates, and Student Programmes were received and processed

by the Recruitment Service in 1995. A steady increase (9%) was observed in the Programmes for Fellows and

Associates, while the situation of applications for the Students Programmes was constant.

The number of man-years of Fellows and Associates suffered a 7% decrease mainly due to limitations in

funding from CERN and external sources.

Personnel Division

The number of Students, however, increased by 12%. This increase was mainly thanks to the contribution

of Austrian funds to the Technical Students Programme. In this context 12 new Austrian Doctoral Students

were offered positions in 1995.

The five-yearly review of the Fellows, Associates, and Students Programmes was approved by Council at

its session in June 1995. This included the following main recommendations:

— to increase the number of Fellowship positions by approximately 10% within the same budget

constraints;

— to.abolish the category of Travelling Fellows;

— to continue the practice of limiting the expenditure for Non-Member State Scientific Associates to

approximately 1% of the Personnel Budget;

— to create a Doctoral Student Programme separate from the Technical Student Programme and maintain

the number of training places for undergraduate students at its 1990 level;

- to announce the availability of training places for young graduate engineers in the various technologies

in which CERN is involved.

Indefinite Contracts

In 1995, fifty-six candidates in professional categories other than that of research physicists were

reviewed. Following final assessment by a CERN-wide review board, the Director-General approved the

award of 39 indefinite contracts. Seventeen cases were left pending. In addition, two indefinite contracts were

granted to research physicists.

Departures in 1995

One hundred and forty-five staff members left the Organization for the following reasons:

Retirement 33

Non-renewal of contract 21

Resignation in the interests of the Organization 69

Other resignations 14

Disciplinary 2

Disability 2

Death 4

Training

The Five-Year Forward Look at Training prepared by the Joint Training Board was approved by CERN

Management in March, together with a series of recommendations aimed at translating these principles into

action in 1995 and subsequent years. The main thrust of the Forward Look is to manage training as part of a

broader human resource policy, fully integrated into the work planning process.

Personnel Division

A new text was prepared to simplify and update the section on training in the Staff Rules and Regulations,

which had not been modified since its introduction in 1980.

The centrally organized training programmes continued to be well supported. There were many new topics

in Technical Training (ranging from the World-Wide Web to turbines for cryogenics) and a significant increase

in demand for both English and French Language Training. Changes were made to Management and

Communication Training in order to tailor the approach and content of the seminars and workshops more

closely to the CERN situation, and this was extended to seminars in presentation and communication for all

CERN guides. The Academic Training programme continued to attract good audiences. While off-site training

continues to be appropriate for individual and/or specialized training, as far as possible volume training is

channelled through the central on-site programmes.

The volume of training followed by CERN staff reached the level of 3.8 man-days per staff member on

average, which represents encouraging progress towards the goal of 5.0.

Health Insurance

The Division continued to take an active part in supervising the health insurance contract with AUSTRIA

Collegialität, which is monitored by the CERN Health Insurance Supervisory Board (CHISB), and comprises

members of both the Management and the Staff Association. Various studies conducted during the year and

discussed in TREF resulted in the reduction of a number of benefits, together with the introduction of direct

contributions in a phased manner by the Organization towards the health costs of CERN pensioners, as

approved by the Finance Committee and Council in December. A progress report on possible cost containment

measures for 1997 will be provided by the Management in June 1996.

Informatics Systems

The introduction, in collaboration with AS Division, of new informatics systems for human resources

administration, payroll calculation, processing of advances and claims, and recruitment activities generated

substantial extra work for staff in the Administrative Services as well as the Recruitment Service. This

involved data correction after the full transfer and also implementation problem solving required in adapting

the new systems to the Organization's personnel procedures.

Modified Swiss Regulations

Modifications by the Swiss authorities to a number of procedures and formalities applicable to various

categories of members of the personnel entailed a major logistics exercise on the part of the Administrative

Services Group. This involved the exchange of some 4600 identification cards and the setting up of additional

procedures and control processes.

Personnel Division

Technical Inspection & Safety

Commission

General Safety Group

The programme of periodic safety inspections in all fields continued, with special attention being paid to

buildings and installations entailing larger risks. The construction, installation, tests and commissioning of

equipment for LEP2, the NA48 experiment and the R&D programme for LHC experiments were followed

closely. Safety discussions for LHC experiments have started. The Group participated actively in tests of

prototype machine components for the LHC and in design studies for new mechanical structures and handling

devices, as well as for electrical and cryogenic equipment and installations.

The Special Health and Safety Committee (CSHS), a permanent body for preventing accidents of outside

firms working on CERN premises, concentrated on the construction of buildings 39 (hostel) and

40 (physicists’ building), and on the transformation of the heating plant on the Meyrin site. The programme to

bring CERN’s machine-tools into conformity with the latest European Directives continued in 1995.

New safety documents were issued and a number of old documents revised to comply with recent

European Directives or Standards. Many ergonomic measurements were made at workplaces and particularly

around noise-generating equipment, to ensure that nuisances for people and the environment are kept below

legal limits. The programme for reducing noise levels from critical installations on the LEP sites was followed

closely.

The Technical Support and Software Support Sections continued to replace obsolete equipment and to

improve operational monitor systems for different TIS Groups. Data transmission and acquisition systems

were upgraded to follow the evolution of accelerator control and CERN-wide transmission systems and to

make all monitor systems more user-friendly. Some new instruments for radiation and environmental

monitoring were developed by the Section and a number of new instruments proposed by industry were

thoroughly evaluated and tested. Technical and software support was given to other TIS Groups for repair,

maintenance and improvement of equipment and for general and database software, office automation and

communication problems.

Technical Inspection & Safety Commission

Table I: Statistics of professional accidents at CERN in 1995

(CERN staff only)

Total declared accidents Number Lost days

(i) Lost-time injuries® 27 592

(ii) Accidents on the journey to and from work?) 7 155

Road accidents on duty with lost time included in (i) 1 8

2) Accidents entailing at least one day’s absence from work

Radiation Protection Group

The draft of the new CERN Radiation Safety Manual (RSM) was ready at the end of 1994, but further

corrections and approval took about a year. The Safety Policy Committee made constructive comments that

led to considerable improvements of the text. The document was approved by the competent authorities in the

Host States in the autumn and signed by the Director-General in December. Both the English and French

versions of the RSM will be printed at the beginning of 1996.

The improvements of the ARCON system in 1994 bore fruit. During the second half of 1995 both the

hardware and software ran without any problem and the new facility of re-booting the ARCONs via Ethernet

only rarely needed to be used. Work to replace the non-standard alarm read-out in the Meyrin Control Room

continued and the new software based on an X-Terminal will be installed during the 95/96 winter shutdown of

the CERN accelerators.

By the end of the year all gates of the two main sites and the BAs of the SPS had been equipped with

monitors for radioactivity and instructions had been issued to the guards on how to proceed if a radiation alert

should occur. The installation of the information and warning panels that go with these monitors is scheduled

for the first half of 1996. A prototype of a new Picomur (instrument to measure low levels of induced

radioactivity) developed by the Technical Support Section of the GS Group became available at the end of the

year. It uses a plastic scintillator and a photomultiplier instead of a GM-tube as a detector. A small working

group was set up to scan the market for electronic pocket dosimeters and to look into the possibility of using

them at CERN.

In the Individual Dosimetry and Calibration Section, a bar-code printer was purchased to equip all CERN

film badges with stickers bearing the encoded name of the person and his/her identification number, with the

aim of monitoring the entry of people into high-level radiation areas. By the end of the year all film-badge

holders had been exchanged for holders equipped with the bar-code, and a satisfactory prototype of the

necessary readers had been built. The latter will be integrated into the SPS access system during 1996. The

result of CERN’s participation in the annual Swiss intercomparison on individual dosimetry again showed

excellent correspondence with respect to the 137C, reference dose but failed to give good results for the

angular dependence of the film badge. The change from VM to UNIX for the procedures to access the Oracle

database of individual dosimetry continued and was essentially terminated by the end of the year. The

implementation of these new procedures will take place in the first half of 1996.


Due to a technical incident during the decoupling of a uranium production target in the ISOLDE facility, a

whole spectrum of fission products including the usual radioisotopes of iodine passed through the installed

filters and was released through the ventilation system into the environment. Although the amount involved

was three orders of magnitude smaller than CERN’s annual release limit, improvements on both the technical

and the radiation protection level are being made to avoid the re-occurrence of such an incident. In parallel, a

reassessment of CERN’s release figures for radioactivity in air and water is under way, in view of the new

isotope-specific dose values given in the 1994 Swiss Ordinance on Radiation Protection and a working paper

issued by the HSK in Switzerland on the calculation of release figures for nuclear power stations.

Based on the experience of 1994, all the necessary precautions were taken, so that the lead-ion run at the

end of the year only led to a slight increase of the radiation levels in the experimental areas of the SPS.

In order to make reliable predictions of radiation doses both inside and outside the LEP tunnel when this

collider is operating at 95 GeV, measurements of the synchrotron radiation levels at 46 and 68 GeV were

performed. The results showed that the measured dose levels at 68 GeV are about a factor of four higher than

those calculated for a machine without any gaps in the shielding around the vacuum chamber (e.g. at the

bellows). These investigations also helped to identify weak spots in the shielding between the machine tunnel

and the service tunnels, such as cable ducts that must be filled when LEP operates at higher energies. The

installation of superconducting cavities inside the LEP tunnel has led to low levels of induced radioactivity

locally. It was found that this activity was due to the conditioning of these cavities, when high-energy photons

give rise to neutrons from (Y,n)-reactions, which in turn react with the cavity material to create radionuclides.

The procedures for generating the monthly and quarterly results of the environmental programme were

converted from REXX to Oracle. During the year, four new water samplers were installed to replace the now

obsolete equipment that had been in service for more than twenty years.

Work on the preparation of the LHC continued in 1995, concentrating on the two experiments ATLAS and

CMS, estimating shielding requirements and radiation doses. Other topics dealt with were the propagation of

muons and the induced radioactivity in rock and in water. As these data, derived from Monte Carlo

calculations, became available, they were incorporated into the environmental impact report of the LHC. A list

defining the requirements in terms of radiation protection equipment both for routine radiation protection

work and the environmental programme around the LHC was elaborated.

In 1995, two further experimental periods at the SPS were scheduled within the framework of the

continuing EU-CERN contract on dosimetry in high-energy stray radiation fields. In addition to the European

participation two teams from the United States took part.

Medical Service

In 1995, the Medical Service performed 2639 medical examinations on 2362 people. Depending on the

subject’s state of health, this general check-up was supplemented by a total of 2363 additional examinations

(ECG, chest X-ray, spirometry and audiogram). Only people exposed to a specific occupational hazard are

examined yearly (shift workers and people with an accumulated exposure to ionizing radiation greater than


100 mSv). The medical check-ups can be complemented by detailed blood tests. The overall state of health of

the staff monitored by the Medical Service is good in view of their relatively high average age.

A total of 4527 people were regularly monitored by the laboratory, 3213 of whom were given blood tests.

Further biological analyses were carried out in 1140 cases. A new automated laboratory system made it

possible to increase the number of analyses on a single blood sample, thus avoiding the need to take additional

samples. In this way, the laboratory determined 10 490 individual biological parameters (cholesterol, glucose,

enzymes), 60% more than in 1994. Quality control is performed once a month by a duly-accredited

organization.

The infirmary responded to 3604 requests for treatment, covering routine first aid, emergencies and sudden

illnesses. Under the doctors’ supervision, the nurses also perform the additional examinations mentioned

above, as well as those relating to working conditions. One nurse assists with the first-aid courses for new

arrivals and the refresher courses (300 new arrivals and 200 summer students). A major tetanus revaccination

campaign was undertaken for workshop and laboratory staff.

Under the auspices of the Rehabilitation Board, the Medical Service plays an active role in the

rehabilitation and redeployment of disabled staff, and has kept up its regular meetings with the Social Service.

Furthermore, it now organizes and performs all vaccinations needed by people travelling on official CERN

business, and provides vaccination information for travellers.

Chemistry, Fire and Materials Group

In the Gas and Chemistry Section, most of the available manpower and resources were devoted to routine

activities including industrial hygiene, gas and chemical safety, water and airborne pollution control and

chemical waste control. The project to replace and eliminate electrical equipment containing polychlorinated

biphenyls (PCB) advanced well. During the year some 62 tons of capacitors were shipped to the incinerator.

Furthermore, a special programme to clear the drains of the Meyrin site of sediments containing PCB was

carried out.

The new apparatus for measuring the flammability of gases and gas mixtures operated satisfactorily and

the flammability characteristics of typical gases and mixtures used at CERN and of special mixtures proposed

by LHC experimental teams were measured. A joint report was published with AT Division on the risk of

explosions in cryogenic liquids exposed to ionizing radiation. Much effort was invested in the revision of the

Flammable Gas Safety Manual and a start was made on the revision of the Safety Code A4 ‘Confined Spaces’.

In the Fire Prevention Section, the project to eliminate old fire extinguishers continued, as well as the

survey of buildings with a fire detection installation over 20 years old. A study on fire prevention and

firefighting in the LHC experimental caverns was completed.

The attached table shows the statistics of activities of the Fire and Rescue Section. The number of ‘fire and

rescue’ interventions amounted to 1280 emergencies plus 146 non-urgent special services. A total of

317 instruction sessions were given and 158 training manoeuvres were carried out. In addition, about

4200 operations of non-fire service related tasks were recorded, such as opening and closing of premises,


“taxi’ transport, firemen’s rounds, etc. These figures show that the frequency of urgent calls is similar to that of

other fire and rescue services, but that the overall level of activity is well above average compared to fire

stations in the public domain. Aside from the interventions, training (both received and given) constituted a

major part of the activities. Over 1100 persons participated in one of the 110 safety courses given by firemen,

and more than 150 first-aiders were either newly trained or attended refresher courses.

A new vehicle (Unimog) was acquired which will be equipped with exchangeable skips containing

pollution and flood-damage control equipment or special extinguishing agents and apparatus. Other important

acquisitions were new helmets fitted with hands-free radio communication systems, and new firefighting

clothing conforming to the latest European specifications. A project was prepared for upgrading the

firefighting installations of LEP, improvements which will also be beneficial for LHC.

In order to cope with the staff reductions, a new duty system was introduced towards the end of 1995

which permits a minimum of 7 firemen to be present during the night instead of the former 10; however, an

on-call service during the night was introduced to maintain the efficiency and safety of interventions.

In the Materials Section the work of the ‘Cable Controller’ remained one of the major activities. In total

129 orders were received, representing 109 km of cables, of which 93 km conformed to the CERN safety

regulations and IS 23. Participation in working groups of the LHC experiments and in the Logistics Advisory

Committee (LAC) helped to identify future needs. The use of fire resistant, halogen-free materials, e.g. cables,

furniture, floor covers, for the new hostel and the physicists’ building was closely followed up. Apart from

routine dosimetry, the work concentrated on improving the estimates of doses and radiation damage for

LEP200 and the LHC machine. Advice was given to the teams preparing the LHC experiments regarding the

choice of organic materials which would withstand high radiation levels.

For the Safety of the LHC Experiments, safety hearings were held during 1995 on the technical proposals

of ATLAS and CMS. These did not reveal any problems which would at this stage prevent approval of the two

experiments for safety reasons. Further hearings will have to be held at all stages of development of the LHC

experiments, with the next step being the technical design reports of specific detector parts.

Table 2: TIS/CFM/FB Group

Overall operations for 1995

Developments between 1986 and 1995

Years 1986 | 1987 | 1988 | 1989 | 1990 | 1991 | 1992 | 1993 | 1994 | 1995

Operations 1854 | 1863 | 2005 | 2437 | 2250 | 2297 | 2110 | 2237 | 2374 | 1998

Firemen’s rounds 2706 | 3708 | 3310 | 3287 | 3060

“Taxi” transport 1314 | 1244 | 1010 918 940 | 1195 | 1075 607 787 734

Opening/closure of premises 167 163 49 71 66 22


Operations

Years 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995

Emergencies

Ambulances 467 458 431 469 220 309 245 256 236 304

Fires 18 17 25 27 12 13 21 12 11 14

Floods, pumping 115 178 221 129 97 123 150 143 63 47

Lifts 77 73 133 270 135 90 96 57 101 127

Emergency shutdowns 25 24 19 37 16 19 38 19 26 25

Problems due to animals 26 23 41 55 43 2] 51 37 29 45

Pollution 12 8 7 11 5 2 2 4 l 4

Automatic alarms

Fire detection 375 466 487 457 332 498 574 695 580 543

Gas detection 147 132 193 113 112 115 140 95 156 78

Flood detection 0 0 2 23 79 2 4 4 0 18

Burglary detection 40 12 42 38 25 13 38 46 19 55

Chlorine detection 0 7 3 9 1 0 l 0 0 1

General 0 4 1 217 146 108 42 21 0 19

Direct prevention

Monitoring in confined spaces 20 27 34 45 26 36 69 97 714 80

Supervision of high-risk work 8 21 37 24 20 17 12 13 9 1

Patrols around the machines 3 2 2 15 16 21 10 1 17 14

Felling of dangerous trees 6 4 6 4 5 2 5 0 3 3

Traffic accident reports 0 0 0 38 32 24 33 29 32 48

Exercises

Auxiliary firemen 6 4 11 18 0 3 7 3 0 0

Professional firemen 1 3 6 69 89 128 109 129 200 139

With local emergency services 0 1 2 1 1 2 5 3 5 0

Training of auxiliary first-aiders 3 4 3 5 4 1 12 3 0 0

Fire detection equipment tests 2 2 1 2 2 0 9 2 2 19

Logistic support

Opening of the customs tunnel 0 47 28 110 144 105 111 102 86 37

Assistance in security 66 325 29 20 7 2

Opening of stores 0 11 30 37 32 5 6 9 7 8

Emergency repairs 28 16 17 24 45 30 27 30 27 49

Protocol service 17 1 4 19 2 45 13 32 21 29

Miscellaneous 458 318 219 171 543 240 251 375 662 289

Training

Courses given by TIS/FB

FB training (working days) 140

Safety briefings 110

First-aid 46

Others 21


Directorate Services Unit

The Directorate Services Unit (DSU) provides administrative and technical support to the Director-

General and the Directors. The head of the unit acts. as secretary to the Directorate and the Management

Board.

Office of the Director-General

DG Secretariat

During 1995, there were 44 meetings of the Directorate and 10 meetings of the Management Board. In

addition, a number of meetings were arranged between the Director-General, the Directors and the Division

Leaders to discuss various aspects of the management of the Organization. The secretariat provided the

Director-General and the head of DSU with secretarial and logistics support.

Relations with Member States

The main activity of the Group was to collect and assess information on particle physics research in the

Member States (its strength, emphasis, organization and funding) and to discuss with delegates and influential

scientists ways in which relations with CERN could be improved. Contacts were established which are being

followed up. Summaries of the status of research in each Member State were continuously updated for use by

the Management. This was carried out in close collaboration with the delegates and with RECFA, which has

shown considerable interest in the work. There were visits to many of the Member States, most often in

connection with other business. Participation in many important committees in the Member States helps the

Group to get a better grasp of the overall situation.

Special attention was paid to the possible extension of the applied science fellowship programme, which is

of great importance in the smaller Member States; to the extension of CERN relations with UNESCO; and to

improving collaboration with the EC, with particular emphasis on the ISTC programme. Efforts were made

not to dissociate particle physics from organizational and funding questions and this was reflected in the

numerous talks given in many countries.

At the request of the Management, a member of the Group made a preliminary report on CERN’s health

insurance scheme (compared to those of other International Organizations in Geneva), and recommended that

an in-depth analysis of the cost structure of health be undertaken as a pre-requisite for more effective

containment of CERN’s future health expenditure. The same member collaborated actively with the DSU-

CP’s Visits Service in devising and implementing a training programme for the public-visits guides.


The Group Leader was an invited lecturer at two meetings and took up important duties with ESA as

chairman of the FPAG and a member of the SSAC. He also continued to chair the Pauli Committee; work on

translation of Pauli’s recently-discovered correspondence and documents is under way and new publications

are being prepared.

Relations with Non-Member States

There were two principal facets to the work of this Service in 1995: meeting with senior visitors to CERN

from many of the Non-Member States; and visits to some of these countries, which were keen to enhance their

links with CERN. Countries visited in 1995 included Japan, Romania, Slovenia, USA, Russia, Armenia,

Pakistan, China and Bulgaria; visits to the Ukraine and to Albania had to be postponed until 1996. In addition,

the Director-General and the LHC Project Leader visited Canada.

Other activities involved preparing Co-operation Agreements or Protocols to existing agreements with

countries which included India, Russia, and Iceland. The leader of these activities also took part in the

Consultation Group on Non-Member State Matters, the CERN-Russia Committee and was Joint Chairman of

the CERN-Dubna Committee.

Council Secretariat

The Council Secretariat made the practical arrangements for two Council sessions, 15 Committee

meetings (Scientific Policy Committee, Finance Committee and Committee of Council), nine meetings of the

Tripartite Employment Conditions Forum (TREF) and seven ECFA meetings (plenary and restricted): in all

some 33 meetings.

The Secretariat co-ordinated the preparation and distribution of 470 documents (see breakdown below).

The number of documents passing through the Secretariat increased by nearly 14% compared with 1994,

mostly due to the considerable extra workload for TREF.

The Office continued to provide secretarial support to the President of Council and to the Chairmen of the

Finance Committee, Scientific Policy Committee and ECFA as well as the different members of these

Committees and TREF.

Document Statistics — Council Secretariat (1995)

Number of Documents

Committee English French German Bilingual Total

Council & Committee of Council 47 47 4 7 105

Finance Committee 103 103 40 6 252

Scientific Policy Committee 17 5 _ _ 22

ECFA 22 _ _ _ 22

TREF 61 8 _ _ 69

250 163 44 13 470


Office of the Director of Administration

On behalf of the Directorate-General and the Administration Divisions (AS, DSU, FI, PE), the Service is

responsible for centralizing the information needed for human and material resources planning, establishing

the annual operation and investment budgets, and managing requests for projects in the sector. It establishes

mechanisms for ensuring that the budget is properly applied and takes all the necessary steps to keep financial

commitments within the set budget limits.

In liaison with the Personnel Division, it centralizes applications for recruitment and administers the staff

complements provided for by the plan for the whole Administration sector. It also handles applications for

annual advancement and co-ordinates the DSU Unit’s MOAS operation.

The Service is responsible for certain central budgets, including that for communications: it provides

administrative co-ordination with the postal and telephone services of the Host States in close collaboration

with CERN’s technical services.

The Office keeps abreast of CERN’s new office automation methods—BHT, EDH, EDHADMIN, HR and

AVCIL-—-and takes the lead in introducing them into the Management Services. In 1995 it also continued its

work in the field of invoicing studies.

Relations with the Host States

In the context of relations with the Host States, the Administration continued to represent the Organization

before the French and Swiss administrative authorities at all levels. It dealt more specifically with the

residence and employment of the spouses and children of members of the personnel, passage through the

tunnel between the sites and across the border, arrangements with the customs and police authorities, steps to

protect property, transport and traffic, the status of contractors and their staff and various administrative

procedures.

Industrial Services Unit

Following the request by the Finance Committee to re-tender all the Industrial Services contracts, and

subsequent to extensive discussions with delegations, a Guidelines paper (CERN/FC/3819) was approved by

the Finance Committee in November, defining the basis for all Industrial Services tendering. A timetable

(CERN/FC/3820) for the tendering was prepared in collaboration with the Divisions and presented at the same

meeting.

Active support was given to the user Divisions in drawing up Market Surveys and specifications for calls

for tender.

The Industrial Services Unit participated with the CERN Legal Services in the review of all standard

documents annexed to calls for tender for Industrial Services. Many of these documents dated from the 1980s.

The Unit worked in liaison with the Monitoring Board to define practical solutions to cases arising from

the implementation of the new Purchasing Policy and Procedures.


Legal Service

The Legal Service carried out its duties as adviser to the Organization. It participated in drawing up

decisions concerning the LHC, in work concerning associate status, in drawing up co-operation agreements

with non-Member States of the Organization and in the revision of the Staff Rules and Regulations.

The Service was involved in the operations of the CERN Pension Fund, with particular regard to

guarantees for pensions in the event of the dissolution of the Organization and legal questions concerning the

management of its assets. It participated in drawing up consultation procedures with the Host States and in

preparations for the environmental impact study of the LHC to be carried out in preparation for the

construction of the LHC in France.

It took part in several internal committees (especially the Safety Policy Committee, the Pensions Group

and the Training Committee) and was active in preparing several of the Organization’s major contracts.

The Legal Service defended CERN’s interests in disputes, with particular regard to appeals by members of

the personnel to the Administrative Tribunal of the ILO; it continued its work in the insurance field and

contributed towards the settlement of commercial disputes.

It handled the EIFFAGE and Partners/CERN arbitration procedure.

Internal Audit Service

The Internal Audit’s work schedule is prepared on the basis of recurrent work— checking the accounts of

the Organization and the Pension Fund at the beginning of the year—and variable work which depends on

matters arising in all operations with financial consequences. The entire work schedule is subsequently

approved by the Management.

As in the past, checking the accounts was conducted jointly with the auditors to avoid any duplication of

work. Apart from investigations and examinations concerning various sectors of the Organization, the Legal

Service also took part in various working groups. Following the changes at the head of the Internal Audit

Service, its duties and operations were reassessed to suit its future tasks.

Strategic Planning Unit

The Strategic Planning Unit (SPU) helps the Management in corporate planning activities. Its tasks are

divided into three related domains: development modelling, carrying out strategic studies, and providing a

consolidated information centre.

SPU provides models for medium- and long-term personnel and financial planning. It is responsible for

editing the medium-term plan of CERN’s scientific activities and budget estimates. This document is approved

annually by the CERN Council.


The strategic studies carried out by SPU cover a wide range of topics closely linked to its primary mission.

These include analysis of the internal resources requested and available at CERN, national advantages of the

Member States in science and technology, applicability of new industrial planning and management

techniques, and studies on purchasing and outsourcing strategies for CERN.

As a spin-off, SPU acts as a consolidated information centre for economic and financial data such as

country-specific indicators and R&D expenditures. SPU acts as a gateway to similar information units in other

organizations such as business schools, research institutes and industry. It surveys information on the

development of human and financial resources in high-energy physics in the Member States.

SPU also provides support to the Industry and Technology Liaison Office in arranging industry visits on-

site and establishing contacts between the interested companies and CERN engineers.

Industry & Technology Liaison Office

Activities in 1995 included:

— participation in following-up the implementation of the recommendations of the FC Working Group on

Purchasing Policy and Procedures;

— assisting industrial liaison officers at CERN and through the participation in information meetings or

visits to firms in their home country;

— _maintaining relations with industrialists from Member States and assistance in establishing contacts

within CERN;

- assessing the possible contribution of industry in non-Member States to the CERN programme;

— providing information on CERN technologies through the World-Wide Web;

— assisting technology transfer actions, in particular through collaborative development projects;

— assisting in Intellectual Property Rights protection;

— assisting external studies on technology transfer;

— maintaining contacts with the European Commission and following the specific R&D programmes of

potential interest to CERN;

— participation in information and training activities relating to the technological spin-offs from particle

physics and their economic benefits, and the applications of particle physics technologies, in particular

the use of accelerators in medicine and industry.


Communication & Public Education Group

The COPE Group, with some 30 personnel, looks after the public image of CERN.

Media & Publications Section

The Press Office had a very busy year, with several major media events including Japan’s contribution to

the LHC, the upgrade of LEP and the sabotage of the PS accelerator.

510 journalists visited CERN — an average of 2 every working day. In addition, a special and highly

successful two-day World-Wide Web conference was held in March at short notice. It attracted

200 international science journalists and information officers.

The Section published a range of new information leaflets on CERN. The decision was made to move away

from brochures, which are difficult to update and expensive to produce, towards a more flexible leaflet format

with a consistent ‘house style’. For the first time, leaflets were produced to encourage the general public to

visit the Laboratory and also to promote the very popular CERN travelling exhibitions. A great effort was

made to include many more news stories in the Weekly Bulletin.

The Photographic Service moved from the main building to temporary accommodation in building 33,

where its staff endeavour to provide the usual high level of service, as far as possible.

The CERN Courier attracted increased advertising support and many authoritative contributions; it

continued to play its role as the international journal of high-energy physics, bringing scientific and technical

developments to a wider audience. A special issue— ‘Applying the Accelerator’ —covering the applications of

particle accelerators was enthusiastically received.

Visits & Reception Section

The revitalized Visits Service welcomed a total of 24 513 visitors in 1995 (16% up on 1994) broken down

as follows:

Visit type 1995 1994 Difference

Saturday visits 13 721 12 218 1503

Weekday visits 9497 7129 2368

VIPs 785 1161 -376 Media 510 566 -56

Total 24 513 21 074 3439


The lower number of VIPs in 1995 may be due to a significant proportion of the 1994 visitors coming to

CERN in the run-up to the LHC approval.

The overall increase in visitors was made possible by building a more solid team of volunteer guides,

enlisted with the help of the Divisions and including a significant number of young physicists. At the end of

the year, the team had 235 volunteers, 140 of whom had followed the two-day training course for guides

which, organized in close collaboration with the Education Services, was the key element in the relaunch of

the Visits Service in 1995. This project will continue in 1996.

Other new features were the introduction of continuous information channels for the guides (press-

cuttings, briefing sessions, tours of the experiments and information on safety), the creation of a Visits Web

page and a series of monthly seminars for CERN guides on various topical subjects, starting with a

presentation by F. Bonaudi entitled ‘CERN as it was: men and decisions that made the Laboratory’. More

informal events helped to keep team spirit high, such as an evening in December with a round table on the

importance of science popularization, featuring senior physicists P. Darriulat, L. Foa and M. Jacob.

The Reception staff participated very actively in the various initiatives launched by the Visits Service and

are now an essential part of the team.

The Shop continued to carry CERN’s image into the homes of our visitors with record sales of souvenirs.

Microcosm & Exhibitions

Microcosm attracted many visitors during the year.

A 3-month study was commissioned with the Science Museum, London, to evaluate Microcosm and

CERN’s travelling exhibition. This resulted in a recommendation to overhaul both exhibitions which was

given the go-ahead by the CERN Management. Work starts in January 1996 and will continue for three years.

At the end of April, the travelling exhibition spent four weeks in Brussels where it was seen by

5000 visitors. In September, a small exhibit on the World-Wide Web attracted a remarkable 25 000 visitors in

five days at the International Market of Advanced Technology in Toulouse. Another 25 000 visitors, including

some 20 000 school and college students, visited the CERN exhibition which spent three weeks in Cracow in

October.

The 1996 travelling programme has been scaled down as work gets underway to modernize the

exhibitions. The main venue will be Berlin for four weeks in June.


CERN Pension Fund

For the Pension Fund, 1995 was marked by considerable activity in the settlement of technical problems

linked to actuarial matters, the services to members and beneficiaries and the examination of financial markets

and investment policy.

The examination of the results of the actuarial review was one of the major subjects for thought and

discussion during the past year. The three-yearly review conducted in 1995 related to the years 1992-1995.

The Fund drew the Organization’s attention to the effects of personnel policy on the Fund’s technical balance.

The considerable reduction in staff numbers, early departures and unequal salary and pensions adjustments

will have an effect on the long-term financial position of the fund. The review resulted in a number of

recommendations which were submitted to the Organization’s bodies. One of the indirect effects of the

actuarial report was an initial increase in the staff contributions, which rose from 9 to 9.37% as from Ist

January 1996.

Regarding benefits, the Fund discussed the expediency of introducing possible distraints on pensions in

favour of third parties. The Council of the Organization, following the recommendation of the Fund’s

Governing Board, recognized the need to allow a distraint on a beneficiary’s pension in favour of a former

spouse in the event of failure to pay the maintenance allowance.

The Fund was closely associated with the continuing work of the special group on reintegration concerning

pension guarantees. Two documents—.a draft deed of establishment of the “Fondation Caisse de Pensions de

l’Organisation Europ&enne pour la Recherche Nucl£aire’ and a draft exchange of letters between the Swiss

Federal Council and CERN regarding the ‘Fondation’ and the tax arrangements applicable to it— were

submitted to the Council of the Organization.

With regard to the investment policy, an examination of the use of derivatives requested and carried out by

an audit company was put before the Governing Board. The Board also took note of an examination of the

ratio between the Fund’s assets and liabilities, which made it possible to assess the probability of the target

yield (6%) being attained depending on the expected yield associated with various investment strategies. The

Fund analysed a great deal of information provided by its global custodian on the results of the investment

policies operated by the external fund managers, whose work had been closely monitored. Changes were

made to the investment instructions. By and large, investment operations were actively continued and the

composition of the portfolio was changed several times. In addition, the data-processing tools used for assets

management were improved considerably. Finally, in the real-estate field, the Fund acquired a building in

Neuilly, near Paris.

The 1995 annual report of the Pension Fund provides detailed information on the various items mentioned

above.


Administrative Support Division

Data Base Applications Group

The Data Base Applications group (AS-DB) is responsible for the corporate administrative applications of

the Laboratory extending from the applications level to the database management systems level. Our main

objective is to provide CERN with an integrated and reliable corporate Information System also accessible to

non-corporate or non-administrative applications (with confidentiality control), thereby giving these

applications total information coherence and accuracy.

The main applications under responsibility of AS-DB include finance, purchasing, human resources,

payroll, materials management, logistics, advance and claims, inventory. These applications are used by over

400 concurrent users (ca. 600 registered) to perform their daily work.

Considering the very limited resources available, we aim at implementing, as much as possible, standard

solutions in a standardized integrated environment (UNIX/ORACLE), and reduce in-house development to an

absolute minimum. This strategy, compared to tailor-made solutions, presents many advantages by enabling us

to:

— significantly reduce the maintenance and development effort within CERN,

— take advantage of the package evolution (functionality and user interface),

— implement new requirements, whenever possible, by making use of already available functionality

within the package.

The disadvantage is that CERN users have to adapt their working practices to the standard solution which

is not always well understood and accepted.

The support of applications in production requires roughly 60% of the available resources (6 FTE). This

work includes providing user support, parametrization of the system, detection and bugs follow-up, testing of

new versions, specification of new requirements, communication with package suppliers, etc.

In 1995, all available resources were allocated to the AIS (Advanced Informatics Systems) project where

major new applications were successfully implemented and consolidated:

— Human Resources application (purchased from Oracle) went into production on 1 March 1995,

according to schedule, after a major effort in the product parametrization and the initial data loading.


— Payroll application (SIGAGIP product purchased from CGlI) also went into production on 1 March

1995 after a significant upgrade of our previous application (from the same supplier) and after the

development of interface tables allowing all Payroll information to automatically map to information

maintained by the Human Resources application, therefore ensuring total coherence.

— Advance and Claims application (developed in-house in view of CERN particularities) also went into

production on the same date. This application, thanks to its close integration with the Human

Resources application, already produced significant productivity gains (mainly by abandoning non-

integrated existing divisional systems, and also by eliminating the need for a second data-entry

previously performed by the Administration).

— PECT (developed in-house in view of CERN particularities) assures an automatic interface between, on

the one hand, the Payroll and the Advance and Claims applications, and on the other hand, the

accounting application Oriac.

— Material Management application for the CERN Stores (TRITON product purchased from Baan/

International) went into production in May 1995. This application, together with its closely integrated

application LIMS (for calculation of replenishment parameters and forecasting) has handled over

200 000 sales order lines since its introduction and over 100 000 self service sales.

— Foundation application (developed in-house) was completely upgraded to accommodate a totally new

structure, hence providing global data coherence by implementing automatic data update across

different applications.

The successful implementation of the above applications enabled the complete phasing out of the old IBM

CERNADP mainframe.

In addition, other existing applications like the Inventory System, GESLOC (space management),

Adressage (external mail), Courier (internal mail), were re-implemented on UNIX /ORACLE and are now

under the responsibility of AS-DB.

Desktop Computer

The group is responsible for all PC and Macintosh general support services for the whole of CERN

(delivery, installation, set-up of software and hardware, diagnostics, repairs, maintenance, etc.). Dedicated

Mac support is also provided for the Director-General and the DSU unit.

General software licences with Microsoft were used to maintain the levels of our standard PC and

Macintosh application software (Word 6.0, Excel 6.0, PowerPoint 4.0, Project 4.0 etc.) as well as limited

licences for Corel Draw and MicroGrafx Designer for the PC. The servers for accessing Macintosh software

were updated and the CD-ROM server for PC software was extended. An additional person was added to

Macintosh support to deal with problems of Mac networking. After due evaluation, the hardware contract was

extended to include a second European supplier. More than 5000 hardware, 3000 software and

450 communication and networking interventions were carried out.


Macintosh

— bought/sold/installed 312 units and upgrades (plus hard disks, printers, scanners, memory, etc.);

— bought and sold 469 software products;

— processed 904 inter-divisional requests and created 336 orders through FI Division;

— installed 20 additional EtherNet cards and communications software.

PC

— bought/sold/installed 378 units and upgrades (+ hard disks, printers, scanners, memory, etc.);

— bought and sold 44 software products and manuals;

— processed 499 inter-divisional requests and created 182 orders through FI Division;

— installed 400 EtherNet cards (Intel Ether Express) and communications software.

Document Handling

Preprint Server

The Preprint Server continued to offer access to HEP-related preprints via WWW. Since its introduction in

1994, the service has been continuously improved. Automatic submission is now possible for all CERN

material and was extended to non-CERN users. Documents are being offered in as many formats as possible

so that they can be read from all standard platforms. Usage of the server averaged around 6000 accesses per

day including some 900 document downloads.

The Preprint Server also offered other HEP-related documents; transparencies from important conferences

were scanned and made available, the CERN Yellow Reports are being given their own WWW pages.

Printshop

The group continued to manage the CERN printshop. Three modern, high-speed printer/copiers from

Kodak, Xerox and Oc& produced approximately 20 million prints between them. The rest of the printing

(about 32 million prints) was done using conventional offset machines.

A colour photocopy/printing service using a Canon CLC 500 produced a total of 68 000 prints.


Desktop Publishing Centres

Both DTPs continued to help CERN authors prepare papers, posters, etc. for publication. A total of

210 documents, containing almost 7000 pages, were treated by the service. The work done included page

layout, production of graphics, proof-reading, copy-editing, and typing.

Library Support

The group continued to provide computing support to the CERN Library. This consisted mainly of the

closer integration of the CERN Integrated Library system (ALICE) and the Preprint Server. A new version of

ALICE has been under test and it is hoped that, during 1996, this will provide a new, user-friendly interface,

via WWW, to the information stored in the CERN Library.

Conversion and Presentation

This section provided a self-service scanning with OCR (Optical Character Recognition) capabilities; a

server for the automatic conversion of PostScript files to PDF format; various file format conversion tools; a

colour printer and programs for producing overhead transparencies with standard backgrounds and formats.

Specialists are available to provide advice on all aspects of document conversion and the use of new

presentation technology.

General Services

Housing

The high occupation rate of the new hostel (Bldg. 39) since it opened in June 1995 has provided proof, if

need be, of the justification of increasing the capacity of on-site accommodation.

All members of the Housing Service, and hence all its activities, have been grouped together in this

building with a view to improving efficiency and convenience for the Service’s clientele.

The text of the Market Survey was prepared as the first step in the tendering process for the industrial

support contract covering all the activities of the Service.

Mail Office

The modernization process continued as planned and should be completed on schedule in 1996 with the

introduction of the new informatics tool for the addressing section and the improved layout for sorting and

distribution, which has been designed to cater for the increased number of distribution points stemming from

the commissioning of the new Physics Building (Bldg. 40).


Negotiations with the commercial services of the host states’ post offices and various specialized private

agencies once again resulted in preferential rates and treatment for CERN based on the quantities of mail

involved. As an indication, the budget for stamp duty was reduced by some 15% in spite of an increase in

volume of 4%.


support contract covering certain activities of the Mail Office.

Site Access and Surveillance

Interphones were installed to connect certain access points to the Meyrin site to the access control centre in

Building 120 from where video surveillance of Gate A has also been made possible.

Lighting conditions at Gates A and C and the inter-site tunnel were improved through the installation of

high-power spot lights.

A number of vehicles parked in such a way as to create hindrance were moved elsewhere after their owners

had been subjected to a considerable amount of pressure. A campaign to clean up on-site car parks in general

resulted in some 28 vehicles being sent for demolition.


support contract covering the guards on duty at the major site access points.

Logistics Services

AIS Project

Materials Management and Logistics

The TRITON software package, from Baan Information Systems (NL), was successfully implemented

during 1995. Some of the major features include:

— the provision of an electronic Stores catalogue with an integrated electronic Material Request accessed

via EDH. It is hoped that the electronic catalogue will be made available on the World-Wide Web

during 1996;

— the introduction of bar coding with laser scanning and packaged distribution in the Self Service Stores;

— the introduction of the Virtual Store where no inventory is carried by CERN, but where the material

requests are transmitted by EDI to the supplier who delivers the items to CERN the next day.

The TRITON application also features an in-house developed Logistics Inventory Management System

(LIMS), and is integrated with the SIRIAC Purchasing application and EDI Gateway.


Stores

The implementation of TRITON had a major effect on Stores operations. Requests transmitted

electronically can be processed and material delivered the same day. All of the stores are managed individually

and in the case of the Self Service Stores the inventory has been reduced by 60%. Average service levels have

increased from 95% to over 96%.

The total value of standardized items issued was 20.7 MCHEF. The rate of turnover was 1.7 and the total

stock value varied between +0.6% and -5.5% of the authorized stock limit of 13.6 MCHF. The level as of

31 December 1995 being 5.5% below the authorized limit.

The standardization section took 155 decisions. As a result 98 new items were introduced and

57 declassified.

Transport and Distribution

The definition of enhancements to SIRIAC Import/Export and Receiving applications were transmitted to

the software supplier for inclusion in the next upgrade due in 1996. The take-up of electronic Shipping

Requests via EDH approached 50%.

During 1995:

— 4477 incoming and 7078 outgoing shipments were handled for the whole of the Organization;

— the Sales Service sold equipment for a total amount of 1.16 MCHF.

Scientific Information Services

Service Production

The desk service was increased from 6 hours per day to 11 hours per day. A new User Services Section was

created. Interlibrary loans can be ordered via a set of forms available on the SI Home Page on the WWW. The

number of ILL requests increased from 1000 in 1994 to 3000 in 1995. The ETH Library is still our main ILL

supplier and the process will be rationalized by using the ILL module in ALEPH. The number of preprint

records processed increased from about 350 per week to about 400 per week (350 from bulletin boards). The

three free photocopying machines in the Central Library produced 1 million copies in 1995, and the fast laser

printer (mainly used for printouts from the text server) produced 20 000 pages per month. About

100 000 documents (CERN publications, reports, Particle Properties Booklets and Review of Particle

Properties) were distributed.

In 1995 acquisitions remained at their 1994 level. A number of CD-ROM updated publications were

acquired. Some electronic journals were purchased in parallel with printed versions, allowing limited access

on the CERN site. This form of publication is growing fast, and includes some important physics journals.


First steps were taken to replace missing literature.

Personnel

The Library staff remains unchanged. In-house training with external speakers took place and the

1995 topics concentrated on interlibrary loans and electronic document delivery. Since December 1995 there

is only one person working in the Archives; a replacement for the Assistant Archivist is being sought.

Library extension

A large building restructuring plan is under way. The ground floor of Bldg. 52 will become the journals

reading room. Work started in October 1995. The plan also includes the restructuring of the current journals

wing in Bldg. 3 and the main reading room on the Ist floor of Bldg. 52. The work is scheduled to be finished

(removal included) by the end of September 1996.

Projects

A full inventory of the books collection was carried out in 1993. This showed an alarming rate of missing

literature (38% of the monographs). The SIPB discussed these results and asked the Library to implement a

more effective access control and to begin replacing missing literature.

Two new series of publications were created: the Open series for all non-divisional documents, and the

Thesis series for all theses prepared under CERN’s supervision or using CERN equipment.

Input for the automated catalogue of the experiment proposals collection was started. A check of

coherence with follow-up has been done between the Central Library and Archives collections.

A study about a CD-ROM LAN was carried out with a selection of suitable equipment. CERN usage

requires that PC, Macintosh and X/terminal have access to the CD-ROM LAN.

The Library was also involved in the preparation of some European Union research projects. These

projects were not funded.

Archive

The CERN Historical and Scientific Archives has continued to increase its collection of material. With a

staff of two, reduced to one at the end of 1995, cataloguing was kept to a minimum. It will be enhanced as

soon as new resources are available. Archives services have been made known by publicity campaigns.

Interviews with CERN senior staff are ongoing.


Library Automation

A long process of migration from the current library automation system to a new UNIX version was

developed. The conversion will take place in 1996 making a new graphical user interface available.

Systems and User Interfaces

Systems & Operations

During the year the section continued to provide system and operational support for the UNIX systems

running all CERN administrative applications. This includes performing the necessary systems and database

backups and recovery operations, user registrations, performance monitoring, capacity planning, installation

of new machines, hardware and software upgrades, etc. It also includes giving system support to the database

administrators in AS-DB.

Continued Oracle Database administration of the EDH and BHT databases, support to EDH and BHT

users with installation, user administration and front line help were also among the services offered.

System support was given to all development machines used in the AS-SU and AS-DB groups

(Macintoshes, PCs and UNIX workstations).

Finally, operation of the CERN-wide QuickMail service continued. The two gateways were upgraded to

support MIME messages. All servers are now located in the server room in Building 5 comprising around

1500 users on 9 machines. This concentration has helped in making the operation of the QuickMail system

easier.

BHT-the Budget Holder’s Toolkit

Several enhancements were made to version 3 of BHT during 1995: Functionality was added to see

transactions ‘in the pipeline’ (purchases requested via EDH, but not yet committed in the financial system

ORIAC). Dependency on CERNVM and Oracle ReportWriter was removed with the introduction of a new

BHT listings sub-system which also offers the possibility to receive BHT listings via email (especially useful

for external teams). Additionally, modifications to the Stores part of BHT were made to coincide with the

introduction of the new Stores Management system.

Following the introduction of Excel 5, and the announcement by Microsoft that the Excel macro language,

in which BHT was originally written, would be abandoned in favour of Visual Basic for Applications, it

became clear that BHT would have to be re-written. This was undertaken by a team from Dubna in

collaboration with the BHT authors. BHT version 4, which will come into production early in 1996, is the

result of this collaboration.

The number of BHT users is over 750 and this continues to rise steadily, in particular visiting teams now

represent around 20% of the BHT user community. Typically 40-50 Budget Holders use BHT daily. To


increase awareness, provide easy access to information, and provide answers to commonly asked questions, a

lot of information has been made available via the World-Wide Web (http://assuwww.cern.ch/bht).

EDH-the Electronic Document Handling System

During the year the Material Request and Stores Catalogue were made available in EDH following the

introduction of the new Stores Management system.

This increased use of EDH within divisions at CERN, and at the end of the year 2500 active users were

creating and authorizing documents with typically 550 users connected daily. In December the 100 000th

EDH document was created illustrating EDH’s increasing popularity.

The MOAS exercise was performed in EDH as a pilot exercise for the AS division.

Version 2.1 of EDH was largely developed during the year. This new version, due for release early in

1996 gives the users a desktop on which they can create and organize icons corresponding to the most frequent

EDH actions. This version gives EDH a very new look and feel.

EDHADMIN, the tool which grants access to EDH and which manages the signature rights database, was

completely rewritten to comply with the relevant CLA decisions.

With the introduction of Oracle HR, CERN-specific functionality was implemented in EDH: support for

part-time calendars, calculation of absence duration, etc.

Many presentations were given throughout the year, and regular workshops were held to allow users to

meet the EDH developers which has proved to be mutually very beneficial. Much information is available

about EDH via the World-Wide Web (http://assuwww.cern.ch/edh).

EDI-KElectronic Data Interchange

An interface with the new Stores Management system was put in place for the existing EDI applications.

Additional EDI messages were defined and communication tests were performed with Angst+Pfister.

New EDI translation and document management software was purchased and installed, and work started to

integrate the software and optimize its use before including new partners.

Translation and Minutes Service

In 1995 the Translation and Minutes Service had to cope with a particularly heavy work-load of minute-

writing for 73 meetings. In addition to minutes for the usual sessions of the Council and meetings of the

Finance Committee, the Committee of Council and the Scientific Policy Committee, other records written

included those for ECFA, the Pension Fund (9 meetings), the Tripartite Employment Conditions (9 meetings)


and the Standing Concertation Committee (21 meetings) as well as for the Annual General Meetings of the

Pension Fund and the Staff Association. The work-load for the Standing Concertation Committee and TREF in

particular increased substantially during the year as a result of the additional meetings in the framework of the

five-yearly review of employment conditions and revision of the Staff Rules and Regulations. The Service was

also responsible for drafting the reports on the monthly Management Board meetings for publication in the

Weekly Bulletin (11 meetings).

On the translation side, the number of pages translated was close to the 1994 level, the work-load

consisting mainly of specifications, documents for the Council and its Commnittees, articles for the CERN

Courier, press releases, and other official administrative and technical documentation. There was also a

substantial increase in the requests by divisions in the administrative sector for linguistic revision of and

drafting assistance on documents for the Council and its Committees.

Organization and Procedures

The Organization and Procedures Section provides the secretariat for the ‘Comite de liaison

Administrative’ (CLA) which is composed of the Divisional Planning Officers (DPOs) and Division Leaders

of the administrative divisions under the chairmanship of the Director of Administration. The CLA is an

important forum for discussion of procedural questions. The committee met five times during the year.

Work on the maintenance and completion of the handbook of administrative procedures continues. This

work is done in collaboration between the Section and the ‘Groupe de Travail sur les Proc&dures

Administratives’ (GTPA) with representatives from the divisions. A member of the OP Section presides the

GTPA. Progress of the handbook has regularly been presented at the CLA. The text of the handbook and much

of the graphics is available on the World-Wide Web for CERN internal consultation.

Members of the Section continue to be actively involved in training and user support around the

introduction of the new AIS Human Resources and Payroll system as well as the system for the handling of

claims payments.

As new forms are being added to the Electronic Document Handling (EDH) system, a number of

procedural problems have been resolved. A generalized procedure for the handling of all OSVCs (Ordre de

Service Valant Commande) and equivalent documents has been devised and is being implemented in EDH.

In collaboration with representative DPOs from the different sectors, a large effort has been made to

clarify, streamline, and document the procedures around the maintenance of data on the administrative

structure of the Organization. In addition to agreed and documented procedures, this has led in particular to

the decision to allocate budgets for multi-divisional projects (i.e. the major accelerator projects and the

proposed z experiments) to the executing divisions and to present budgets and expenditure accordingly.


Technological Developments at CERN

in 1995

Accelerator Technology

Subject: A composite vacuum barrier for

the LHC short straight section

Collaborator: FIBERTECNIC (ES)

Contact: P. Rohmig/MT-ESH

Reference: CERN MT/95-14 (ESH), LHC

Note 363

The SSS cryostat contains a barrier for

sectorization of the insulation vacuum. The

vacuum barrier is mounted between the helium

vessel and the vacuum enclosure. Its functions are

to limit the spread of any helium leaks and to

facilitate leak detection and the pumping-down

from atmospheric pressure. During the

installation of the LHC, the vacuum barrier

permits independent testing of the half-cells, thus

enabling higher installation rates. In parallel to a

conventional barrier made out of austenitic steel,

a composite-material barrier was developed,

taking advantage of the lower thermal

conductivity of glass fibre reinforced epoxy resin

so as to obtain a low cost product for the LHC.

Subject: Laser ion study

Collaborators: Czech Academy of Sciences

(CZ), Institute of Plasma Physics

& Laser Microfusion, Warsaw

(PL), ITEP Moscow (RU),

TRINITI (RU)

Contacts: H. Haseroth & H. Kugler/

CERN-PS

Reference: Memorandum of Understanding

8.11.1993

With future requirements in mind, in particular

for the LHC, the potential of laser ion sources for

the production of highly charged ions is being

studied in collaboration with two Russian

institutes (ITEP and TRINITI). We are also

collaborating with the Czech Academy of

Sciences, which has a big iodine laser (capable of

producing ultra-short pulses) and where

collaboration has started on different experiments

(see also the Research & Development section in

the PS Division chapter), together with the

Institute of Plasma Physics & Laser Microfusion

in Warsaw.

Subject: Consolidation of ECR ion

source

Collaborator: GANIL, Caen (FR)

Contact: H. HaserotW/CERN-PS

Reference: Annual Report 1992, Vol. 2,

p. 105

Experiments and tests with an Electron Cyclotron

Resonance (ECR) ion source.

Subject: Consolidation of Lead Linac

Ä (Linac 3)

Collaborators: GANIL, Caen (FR), GSI

Darmstadt (DE), Centre of

Advanced Technology, Indore

(IN), INFN Legnaro (IT) & INFN

Turin (IT)

Contact: H. Haseroth/CERN-PS

References: Protocol with CAT signed on

11.9.92; Protocol with IN2P3

signed on 11.3.91

Construction of a dedicated ion linac to

accelerate lead ions.

Technological Developments at CERN in 1995

Subject: Radiofrequency gun electron

sources

Collaborator: Paul Scherrer Institute (CH)

Contacts: P. Pearce & L. Rinolf/CERN-PS

Collaboration agreement

No. K 226/PS

Reference:

Participation of PSI staff in CTF activities

(theoretical studies, computer simulations,

experimental work, construction and test of

equipment). Production of two 35MW RF

sources (one for PSI, one for CERN). Investigate

possible performance limits of both thermionic

and photocathode RF guns.

Subject: CLIC Test Facility

Collaborator: Uppsala University (SE)

Contact: H. Brau/CERN-PS

Reference: PS/LB 10.6.93, Proposal of

Collaboration between Uppsala

University & CERN

Design, study, production and test of two

subsystems to be installed for operation on the

CTFE A beam instrumentation monitor, a

magnetic bunch length compressor.

Subject: Design and running of a

radiofrequency gun for a

250 MeV s.c. linac

Collaborator: Research Center Rossendorf,

Dresden (DE)

Contact: R. BossarUCERN-PS

Help in the designing and running of a

'radiofrequency gun for a 250 MeV s.c. linac.

Subject: Know-how on electron linacs

Collaborator: Sincrotrone Trieste (IT)

Contact: L. Rinolf/CERN-PS

Reference: Agreement No. K 243/PS

Make available CERN’s know-how on electron

linacs and in particular in the field of pulsed

klystron modulators.

Subject: SETUP and Recovery Packages

Collaborator: PNPI, St Petersburg (RU)

Contacts: G. Daems & J-M. Bouche/

CERN-PS

To provide the CERN PS Control system with a

software package for the SETUP and Recovery of

control elements. The SETUP software is based

on object-oriented programming, together with a

procedural knowledge representation (rule-based

process). SETUP is used mainly after a power

failure, a shutdown, the replacement of a faulty

hardware component, and for resetting faulty

equipment. SETUP operates today on more than

3000 devices and is used daily by the operators.

Subject: Data Browser Editor

Collaborator: IHEP. Protvino (RU)

Contacts: G. Daems & J-M. Bouche/

CERN-PS

To provide the CERN PS Control system with a

general tool which gives the possibility to

maintain the operational values stored in the data

tables of the software modules that control the

equipment. With this tool, one can edit, save,

store, compare the current operational data, the

regularly saved values and the so-called

references.

Subject: UNK/U70 Control Systems

Collaborator: IHEP Protvino (RU)

Contacts: F. Perriollat & H.D. Lustig/

CERN-PS

Collaboration and advice on building the UNK

control system and renovating the control system

of the U70 complex. In 1995, most of the effort

was devoted to the preparation of the update of

the U70 control system. It is intended to provide

the U70 complex with a uniform control system,

based on the so-called ‘standard control model

for accelerators’. During the year, a number of

IHEP collaborators contributed to software and

hardware developments in various CERN

Divisions.


Subject: Software sharing and

Applications of software

technologies

Collaborators: ESRF Grenoble (FR), Elettra

Trieste (IT), BESSY Berlin (DE),

DESY, Jülich (DE), CEBAF

Newport News (USA)

Contact: F. Di Maio/CERN-PS

To share experience in applications of advanced

software technologies (object-oriented

programming and distributed client/server

architecture) to accelerator control systems.

Study convergent solutions for Object Models

and Application Programming Interface (CERN-

PS and ESRF). Exchange software components:

prototype of porting CEBAF’s equipment access

on top ofthe CERN PS Control system.

Subject: Synchronization of the different

operations of the CERN PS

Collaborator: MSZKI Budapest (HU)

Contacts: P. Skarek & J. Lewis/CERN-PS

To provide a tool to verify the description and

synchronization of the different operations of the

CPS accelerator complex, as defined in the BCD

(‘Beam Co-ordination Diagram’). The software

package contains a rule-based consultant, which

verifies the validity of the required schedule

(BCD Checker), plus a rule editor.

Subject: Pseudo-spark switch

development for the LHC beam

dumping system

Collaborator: University of Erlangen (DE)

Contacts: H. Riege & G. Schröder/

CERN-SL

Reference: $SL/94-5 (BT)

Fast-high power switches (35kV, 30kA) are

needed to pulse the LHC beam dump kicker

magnets. The kicker magnets extract the

circulating beam in one revolution and dump it on

an external absorber. Two development paths are

being pursued in parallel. First, pseudo-spark

tubes are being developed employing 2-gap

ferroelectric triggering. Second, special-geometry

high-power GTO-thyristor switches are used

based on a commercially emerging technology.

Subject: Expert alarm system for entry

identification

Collaborators: Glasgow Caledonian University

(GB) & Lebedev Institute (RU)

Contact: F. Chevrier/CERN-SL

An expert system is being developed for

identification of intruders in an access-restricted

area. The system comprises posture-analysis of

the intruder and comparison of the generated

image with authorized profiles. The analysis is

based on sophisticated neural network algorithms

developed by the Lebedev Institute and the

integration work is being carried out by Glasgow

Caledonian University. The contribution of

CERN focuses on the expert alarm part which has

already been used in other CERN applications

such as detector gas monitoring systems.

Subject: Electrostatic beam separators

for LEP2

Collaborators: CEA (FR), AEA (GB), Farmsum

Assoc. (GB), Aston University

(GB) Contacts: W. Kalbreier & B. Goddard/

CERN-SL

Reference: SL/Note94-I15(BT)

The upgrading of LEP to LEP2 will nearly

double present collision energies up to 90 GeV.

The synchrotron radiation at higher energies

causes beam-induced sparking which requires

modifications to the present electrostatic beam

separators. The project focuses on better

insulating properties in materials, in particular

those of ceramics. Ion implantation is first

applied on ceramics to control the insulating

properties and the ceramic components are then

submitted to high-voltage breakdown conditions

to further study their performance. The project

has now reached the prototype stage. These will

be tested in LEP in 1996.


Subject: Network on strong-current

photo-emissions and high-

brightness injectors

Collaborators: CEA (FR), LAL (FR),

4 universities (FR), FORTH/

IESL Heraklion (GR), ENEA

(IT), INFN Frascati (IT) &

Twente University (NL)

Contact: G. Suberluc/CERN-PS

Exchange of information (simulations and

measurements) on performances of various

photocathodes and associated lasers for high-

brightness photo-injectors.

Computing

Subject: Central Simulation Facility

Collaborator: Hewlett-Packard (US)

Contact: H. Renshall/CERN-CN

In a joint project with Hewlett-Packard, the

Central Simulation Facility was extended from

16 to 25 HP9000/720 workstations.

Subject: Nu Thena Foresight

Collaborator: Nu Thena Systems Inc. (US)

Contact: L. Pregernig’CERN-CN

References: Contract No. K 230/CN;

Amendment No. ] (extension

until 31.12.94)

A collaboration agreement was signed with Nu

Thena Systems Inc., Virginia, USA for common

development of extensions to Nu Thena’s

Foresight system simulation package in return for

additional free software licences for the use of

this very interesting product at CERN.

Computing & Networking

Subject: WebMaker, converter of

FrameMaker documents to

www

Collaborator: none, but the product was

transferred to the company

Harlequin Ltd that made it into a

commercial product now selling

for 599

Contact: B. Roussea/CERN-ECP

Reference: B. Rousseau and M. Ruggier,

"Writing Documents for Paper

and WWW. A Strategy based on

FrameMaker and WebMaker’,

Presented at the First

International WWW Conference,

Geneva, May 25-27, 1994

The combination of WebMaker and FrameMaker

enables the simultaneous publishing of both

printed and WWW versions of a document.

WebMaker converts FrameMaker documents and

books to a hypertext network of HTML files.

Subject: LIGHT, a software

documentation system based on

www

Collaborators: ALEPH Offline; a US software

technology company has recently

proposed to collaborate

Contact: B. RousseaWCERN-ECP

A. Aimar, M. Aimar, M. Cattaneo,

P. Comas Illas, A. Khodabandeh,

P. Palazzi, B. Rousseau &

M. Ruggier, ‘Using WWW to

Improve Software Development

Reference:

and Maintenance: Application

ofthe LIGHT System to ALEPH

Programs’, Presented at

Computing In High Energy

Physics, Rio de Janeiro,

Sept. 18-22, 1995


Programmers who develop, use, maintain, and

modify software are faced with the problem of

scanning and understanding large amounts of

documents, ranging from source code to

requirements, analysis and design diagrams, user

and reference manuals, etc. This task is non-

trivial and time-consuming because of the

number and size of documents, and the many

implicit cross-references that they contain. In

large distributed development teams, where

software and related documents are produced at

various sites, the problem can be even more

severe. LIGHT, LlIfe cycle Global HyperText, is

an attempt to solve the problem using WWW

technology. The basic idea is to make all the

software documents, including code, available

and cross-connected on the WWW.

Subject ALEPH FSM-2, the new

version ofthe ALEPH online

Finite State Machine

Collaborators: ALEPH Online

Contact: A. Aimar/CERN-ECP

Reference: A. Aimar, OÖ. Carmona, B. Jost,

J. Harvey and P. Mato,

'Representing System Behaviour

with Dynamic Models and

Executing them: The New

ALEPH Finite State Machine‘,

Presented at Computing in High

Energy Physics, Rio de Janeiro,

Sept. 18-22, 1995

A new FSM software for ALEPH online has been

implemented. The functionality is extended in the

direction of the OMT Dynamic Model. The new

machine is data driven, designed with OMT,

programmed in C++, and reusable by other data

acquisition and control systems.

Subject: Templates for User

Requirements and Software

Requirements a la ESA

Contact: M. Ruggier/CERN-ECP

Reference: URL = http://www.cern.ch/

CERN/Divisions/ECP/IPT/

DocSys/PSS05

The PSS-05 Software Engineering Standards

(SES) developed at the European Space Agency

(ESA) are intended as a set of guidelines for

building good software. PSS-05 requires that a

number of documents, covering the entire life

cycle of a software project, be produced. To

ensure completeness, each of these documents

should follow a predefined structure. The goal of

the FrameMaker and WebMaker templates is to

aid in the application of the standards by easing

the production of the documents required by

PSS-05. Each document template contains the

predefined sections as specified by PSS-05. The

FrameMaker templates contain a comprehensive

set of predefined formats, from which both a high

quality printed version and aWWW version may

be automatically derived.

Subject: GPMIMD-2

Collaborators: European Meteo and Climate

Centre (FR, GB, DE), CERFACS

(Centre Europeen de Recherche

et Formation avancee en Calcul

scientifique) Toulouse (FR),

Meiko (GB), Parsys (GB) &

Telmat (FR)

Contacts: F Gagliardi, E. MceIntosh &

L. Robertson/CERN-CN

R. Bock & A. Norton/

CERN-ECP K. Peach/CERN-PPE

Installation of a CS-2 MPP computer from PCI

(Industrial consortium formed by Meiko, Parsys

and Telmat) at CERN as part of the EC high-

performance computing initiative.


Subject: Software

Collaborator: Framatome Div. Ingevision (FR)

Contact: $. Oliger/CERN-ST

Reference: Convention No. K 138/AC-DI

Utilization and exploitation of CERN software

(GRLI and CHEM) to develop a Framatome

product.

Subject: PAW (Physics Analysis

Workstation) and PIAF

(Parallel Interactive Analysis

Facility)

Collaborator: Hewlett-Packard, Grenoble (FR)

Contact: O. Couet & T. Osborne/CERN-

CN

Reference: Contract No. K 254/CN,

Technology Transfer Licence

Agreement

Licence to Hewlett-Packard interested in the use

of PIAF/PAW technology for interactive

treatment of large databases for Telecom servers.

Subject: Demonstration of fast parallel

architectures for image

processing

Collaborators: Univ. of Mannheim (DE), NBI

Copenhagen (DK), IHEP

Protvino (RU), JINR Dubna &

Inst. Engin. Cybernetics

Minsk (RU)

Contact: R. BocVCERN-ECP

Subject: Fibre channel tester

Collaborator: KFKVRMKI (HU), Hewlett-

Packard Geneva (CH)

Contact: E. van der Bi/CERN-ECP

A fibre channel tester has been developed and is

now commercially available. This project was a

collaboration between CERN, RMKI and

Hewlett-Packard/Geneva. This test system has

several working modes: single and double line

monitor, signal generator, N_Port emulator,

fabric tester and fabric emulator. Work is under

way on building a higher speed version of this

tester which can also be used to test the behaviour

of fabrics under load. The tester is now being

sold, and is used already by Hewlett-Packard to

test their fibre channel chips and switches.

Controls

Subject: ECPS Working Group on

Operational Protocols

Collaborators: CEN, Saclay (FR), CRN,

Strasbourg (FR), CRPP-EPFL,

Lausanne (CH), Daresbury

Laboratory, Warrington (GB),

ESRE, Grenoble (FR), GANIL,

Caen (FR), GSI, Darmstadt

(DE), HMI, Berlin (DE), KFA,

Jülich (DE), IHEP. Protvino

(RU), KEK, Tsukuba (JP), LNE

Frascati (IT), PSI, Villigen (CH)

& Sincrotrone, Trieste (IT)

Contacts: G.P. Benincası/CERN-PS,

P. Burla/CERN-SL, P. Strubin/

CERN-AT

The working group defines standard operational

interfaces between the controls of various

families of devices (power converters,

instrumentation, vacuum, etc.) and the more

general controls performed by the operators in

the central control rooms, e.g. through

workstations. Defining such operational

interfaces is a necessary step towards more

rational and more economical control systems.

Around 1000 devices are currently controlled

using these standards at the CERN PS, whilst

CRPP-EPFL (Lausanne, Switzerland) applied

them to control the vacuum of their tokamak.

They have been recommended for the controls of

the LHC.


Cryogenics

Subject: Cryogenic support posts for

LHC magnets

Collaborator: CASA, Constructiones

Aeronauticas SA (Division

Espacio) (ES)

Contact: M. Mathie/CERN-MT

Reference: Contract 193/MT-LHC

Study, manufacture and delivery of three

prototypes of support posts for the LHC dipole

magnets. These posts are made of fibre-glass

composite material, using the Resin Transfer

Moulding system, in order to optimize the

production cost of large quantities, while keeping

the heat inleak very low at cryogenic

temperatures.

Subject: BetaTest program for MOD 300/

MASTER/ADVANT software

and hardware

Collaborator: ABB Sweden

Contact: H.K. Kuhn/CERN-AT

Reference: Letter of Agreement ofa Beta

Program, Contract B 983.00

To verify that the product will do what it is

designed to do through testing in a real-time

situation at a customer site.

Detector Technology

Subject: Development of

superconductors for large

magnelts

Collaborators: CEA Saclay (FR), RAL (GB),

Genoa University (IT), General

Invest (Slovakia), LMI (IT),

Alsthom Belfort (FR), Brugg

Kabelwerke, Cables de

Cortaillod and SCSC (CH)

Contact: P Lazeyras/CERN-PPE

High-purity aluminium stabilized conductors

with performance well beyond present standards

are required for the magnets of ATLAS and CMS.

For CMS, an additional mechanical

reinforcement by an aluminium jacket is needed.

An R&D programme was set up to study the

industrial feasibility of various options of

conductor fabrication and to test the performance.

Subject: Development of mass

production technology for

PbWO, scintillation crystals

Collaborators: NR Minsk (Belarus), IHEP

Protvino (RU), Bogorodysk

Plant, Tula (RU), CEA Saclay

(FR), LAPP Annecy-le-Vieux

(FR) Contact: P. Lecog/CERN-PPE

References: International Science &

Technology Centre Moscow,

Project No. 354-R; CERN/LHCC

96-19

Full scale investigation of solid-state

characteristics of PPWO, scintillation crystals for

use in the CMS and ALICE electromagnetic

calorimeters and development of large-scale

(over 50 000) production technology using the

Czochralski procedure.

Subject: Further developments of hybrid

photodetectors

Collaborators: RD7 Collaboration and part of

the RDI19 Collaboration with

their industrial partners, DEP

(NL), INFN (IT), Preciosa (CZ),

UCI (FR), PPE OF- and TA2-

groups.

Contacts: C. D'’Ambrosio and T. Gys/

CERN-PPE-TA2

(i) JIEEE Trans. Nucl. Sci. 42

(1995) 130; (ii) Nucl. Instrum.

Methods Phys. Res. A359 (1995)

618; (iii) JIEEE Trans. Nucl. Sci.

42 (1995) 2221

References:


A new class of photodetectors (hybrid

photodetectors) has been developed which

surpasses traditional photomultiplier

performances. Their anode can contain from one

silicon diode (hybrid photomultiplier tubes) up to

a few thousand silicon pixels with integrated

electronics (imaging silicon pixel array tubes).

These detectors are single-photon and position

sensitive and have already been applied to count

photons (i), to image particle tracks in

scintillating fibre trackers (ii), and to detect, by

means of a suitable scintillator, gamma- and beta-

rays over a wide range of energies (iii).

Applications are in high-energy physics

(scintillating fibre trackers, RICH detectors, etc.)

as well as in astrophysics and biomedical fields

(g- and b-cameras).

Subject: Technology for manufacturing

microstrip gas chambers

Collaborators: RD28 Collaboration, SURMET

Co. Burlington, MA (US) and

IMT Masken und Teilungen,

Greifensee (CH)

Contact: F. SaulVUCERN-PPE

Reference: CERN/LHCC 96-18

Microstrip gas chambers are novel detectors

capable of withstanding very high particle rates

and radiation levels. The technology makes use of

commercially available thin glass, coated with a

sub-micron diamond-like layer on which the

MSGC pattern is etched by photolithography. The

coating, made by low-pressure plasma-assisted

chemical-vapour deposition makes use of a

proprietary doping process (developed by

SURMET) to control the surface resistivity in a

wide range of values (10° to 1010 Q per square),

depending on the application: the process is

cheap, allows one to obtain large areas of uniform

resistivity and improves the surface quality of the

detectors (diamond coating is a standard

industrial process for tool hardening). An

alternative approach, coating with the diamond-

like layer MSGC patterns already manufactured,

is also being studied.

Subject: Cryogenic temperature

measurement for large

applications

Collaborators: RV-Elektroniikka Oy Picowatt

(FI), Helsinki University of

Technology, Low Temperature

Laboratory (FI), Institute of

Particle Physics Technology (FI)

Contacts: T. NiinikoskVUCERN-PPE

Reference: CERN Preprint CERN-PPE/96

A resistance thermometry system has been

developed for the acquisition, control and

monitoring of temperature in large-scale

cryogenic applications. The resistance of the

sensor is converted to a voltage using a self-

balancing AC bridge circuit featuring square-

wave excitation currents down to 1nA. The

system is easily scalable and includes intelligent

features to treat special situations such as magnet

quenches differently from normal operation. An

8-channel prototype was successfully operated in

the tests of superconducting microstrip line

detectors (RD39).

Detectors

Subject: Development of electroslag

welding process

Collaborator: TTS/ESAB AB, Drobak (NO)

Contact: A. Herve/CERN-PPE

Reference: Agreement No. K 292/PPE

Common development of the Electroslag

Welding Method of thick (up to 60cm) iron

plates. CMS welding test development.


Electronics for Detectors

Subject: RD23: Optical links for LHC

detector front-ends

Collaborators: RD23 Collaboration &

Industrial partners: GMMT -

GEC Marconi Materials

Technology (GB), Italtel (IT),

Europtics (GB), IBM-

Roeschlikon (CH)

Contacts: G. Stefanini & F. Vasey/

CERN-ECP

References: (i) IEEE Trans. Nucl. Sci., NS-42

(1995) 873; (ii) Proc. ofthe 1st

Workshop on Electronics for

LHC Experiments, Lisbon,

Sept. 11-15 1995, CERN/LHCC/

95-56 pp. 175-179

The aim of this project is to develop fibre optic

links for transferring signals from the front-end

electronics to the readout stations in LHC

detectors. Radiation-hard, low-power

transmitters, for analog and digital applications

have been developed based on electro-optic

semiconductor reflective modulators. Hybrid

transceivers are being developed using passive

components with silica-on-silicon waveguides.

Directly modulated laser diodes (discrete/arrays)

are also being investigated. Performance and

system aspects of fibres and connectors are

evaluated.

Subject: SLATE, The Second Level

Architecture and Trigger

Emulator

Collaborators: CERN, Royal Holloway and

Bedford New College (GB),

RMKI (HU)

Contacts: R. A. McLaren & R. var der

FlugV’CERN-ECP

http://www.cern.ch/HSI/hippi/

datagen/slate/slatehrd.htm

Reference:

SLATE is used in testing second-level trigger

systems by emulating data from a detector. Event

data and timing information are loaded into a

VMEbus-based memory and then, on receipt of a

trigger signal, ‘events’ are output at 100 Mbyte/s.

Daughter boards allow different physical media

to be used on the output. SLATE is commercially

available from KFKI-MSzKI Laboratory

Automation Department, Hungary.

Subject: The NA48 Fibre Optic Link

Collaborators: CERN, Dr Struck (DE)

Contacts: P Brodier-Yourstone &

R. A. McLaren/CERN-ECP

Reference: ‘A 10 Mbyte/s Fibre Optic Link’,

IEEE Trans. Nucl. Sci., Vol. 42,

No. 4, August 1995 (ISSN 0018-

9499), http://www. cern.ch/HST/

Scs/applic/na48/na48.htm

The final NA48 data-acquisition system will use a

total of seventeen optical links to move the

detector data 200 m to the control room. The

links use fibre channel components with a simple

protocol which includes flow control, in situ tests

and error detection. They were developed at

CERN and are commercially available from

Dr Struck, Hamburg.

Subject: TURBOchannel to HIPPI

Interface

Collaborators: CERN, Digital Equipment Corp.,

& Hytec

Contacts: R. A. McLaren & A var Praag/

CERN-ECP

Reference: ‘Data Transfer and Distribution

at 70 Mbyte/s’, CERN/ECP

93-7, 19 July 1993. Presented at

IEEE RT 1993, http://

wwn.cern.ch/HSI/hippvV/applic/

applic_NA48.html

The NA48 experiment uses an event builder to

concatenate data received via the optical links

into single events. The output of the event builder

is connected to a HIPPI switch which distributes

the data to one of three DEC workstations. The

HIPPI interface to the workstations was

developed at CERN and is commercially

available from Hytec, England.


Subject: PCI to HIPPI Interface

Collaborators: CERN, Digital Equipment Corp.

Contact: A. van Praag/CERN-ECP

‘Overview ofthe Use ofthe PCI

Bus in Present and Future High

Reference:

Energy Physics Data

Acquisition Systems’, PCI’95

Conference Proceedings, March

1995, pp. 83-88, Annabooks,

11838 Bernardo Paza Court, San

Diego, CA 921128-2414, http://

www.cern.cW/HSl/hippi/applic/

pcihippivpcihippi.htm

The present workstations used by NA48 use

TURBOchannel as an VO bus. Future DEC

systems will be based on the PCI. This

development will replace the present

TURBOchannel to HIPPI interface.

Subject: S-LINK, A Data Link Interface

Specification

Collaborators: CERN, see WWW for list of

collaborating institutes

Contacts: E. var der Bij & R. A. McLaren/

CERN-ECP

Reference: http://wwn.cern.cWHST/s-link/

In the Technical Proposals for ATLAS, CMS and

ALICE there is a requirement for thousands of

data links. The S-LINK is a new concept which

should provide the benefits of standardization

without the limitations. The S-LINK specification

defines, at both ends of the link, a simple FIFO-

like user interface which remains independent of

the technology used to implement the physical

link. The physical link provides transfer of data

and control, error detection, optional flow control

and test facilities.

Subject: High Speed Links and Switches

(MACRAME and ARCHES EU

Projects)

Collaborators: Esprit Projects: SGS$ (FR),

Dolphin (NO), Bull (FR)

Contacts: R. Dobinson/CERN-ECP

Development of the IEEE 1355 standard for high

speed links and switches for use in LHC data

acquisition and triggering applications which will

involve large numbers of communicating

microprocessors. CERN’s prime role in the two

projects is to design and build large switching

configurations and test them with different traffic

patterns corresponding to the needs of both its

industrial partners and physics experiments.

Subject: RDI17: Ultrafast readout of

scintillating fibres using

upgraded position-sensitive

photomultipliers FAROS

Collaborators: LAPP Annecy (FR), Iowa Univ.

(US), INFN Messina, Trieste

and Udine (IT), IHEP Serpukhov

(RU) FNAL (US) & Univs. of

Kyoto and Osaka (JP)

Contact: V Agoritsas/CERN-PS

Reference: CERN/DRDC/Y91-8 DRDC/

P 25, 7.3.91

Study to improve the performance of position-

sensitive photomulipliers and realization of an

ultrafast readout device of scintillating fibres.

Subject: RD31: a high-performance

data-driven event-building

architecture based on an

asynchronous self-routing

packet-switching network

Collaborators: Alcatel Bell Telephone, Antwerp

(BE), Hewlett-Packard, Geneva

(CH), Centre d’Etudes de Saclay,

Gif-sur-Yvette (FR),

Massachusetts Institute of

Technology, Cambridge (US),

Royal Inst. of Tech., Stockholm

(SE), Institute of Radiation

Sciences, Univ. of Uppsala (SE),

National Laboratory for High

Energy Physics (KEK) (JP)

Contacts: J-P Dufey & M. Letheren/

CERN-ECP


References: (i) CERN/LHCC/95-14;

(ii) D. Calvet et al., ‘A Study of

the Performance Issues of the

ATLAS Event, Selection System

based on an ATM Switching

Network’, IEEE Trans. Nucl.

Sci., Vol 43, No. I (Feb. 1996);

(iii) M. Costa et al., ‘An ATM-

based Event Builder Test

System’, Proc. of the Ist

Workshop on Electronics for

LHC Experiments, Lisbon, Sept.

11-15, 1995;

(iv) M. Costa etal., ‘Results from

an ATM-based Event Builder

Demonstrator’, Proc. ofthe

IEEE Nuclear Science

Symposium, San Francisco, Oct.

1995, Subm. to IEEE Trans. on

Nucl. Sci., Conference issue

A research and development project investigating

a new approach to data acquisition based on the

use of Asynchronous Transfer Mode (ATM)

packet-switching network technology.

Commercial, scalable, ATM switching fabrics

and processor interfaces are being evaluated as

potential building blocks for constructing event

builders for the LHC experiments.

Subject: Integrated Time-to-Digital

Converter ASICs

Collaborators: ES2, Rousset (FR), CAEN,

Viareggio (IT), CMP

Grenoble (FR)

Contacts: J. Christiansen & A. Marchioro/

CERN-ECP

J. Christiansen, ‘An integrated

CMOS 0.15 ns Digital Timing

Generator for TDC’s and Clock

Distribution Systems’, IEEE

Trans. Nucl. Sci., 42 (1995) 753

Reference:

Multi-channel TDC integrated circuits in CMOS

technology and VME boards are being developed

for drift-time measurements in LHC muon

detectors (bin size - 0.7 ns) and for particle time-

of-flight measurements (r.m.s. resolution =

50 ps). The time-measuring circuit uses a delay-

locked loop.

Subject: Timing, trigger and control

receiver ASIC for LHC

experiments

Collaborators: ES2, Rousset (FR), Univ. of

Padua (IT)

Contact: A. Marchioro/CERN-ECP

Reference: J. Christiansen et al., ‘Receiver

ASIC for Timing, Trigger and

Control Distribution in LHC

Experiments’, Proc. ofthe IEEE

Nuclear Science Symposium, San

Francisco, Oct. 1995 (to appear

in IEEE Trans. on Nuclear

Science)

The TTCıx is an ASIC dedicated to the

distribution of timing, trigger and slow control

information in the LHC experiments. This

integrated circuit is designed in ES2’s 1.0 mm

CMOS technology. It regenerates a very low jitter

clock and other information from a passive

optical distribution network and delivers this

information to the front-end chips and modules.

Subject: Radiation hardness of silicon

detectors

Collaborators: Canberra (BE), Micron

Semiconductor (GB), Eurisys

Mesures (FR), Topsil (DK), INR

Kiev (Ukraine), JINR Dubna

(RU), LPN Montreal (CA),

University of Florence (IT)

Contact: F. Lemeilleu/CERN-ECP

Reference: $. Bates et al., "Damage induced

by pions in silicon detectors’,

Nucl. Phys. B (Proc. Suppl.) 4

(1995) 510

Studies of effects induced by high dose neutron,

proton and gamma irradiation on the performance

of silicon diode detectors in view of applications

in LHC experiments.


Subject: Hybrid and monolithic silicon

micropattern pixel detectors

Collaborators: Canberra (BE), CSEM (CH),

Faselec (CH), IMEC (BE),

Mietec (BE), GEC-Marconi

(GB), Smart Silicon Systems

(CH), RD19 Collaboration

Contacts: E. Heijne & M. Campbell!

CERN-ECP

References: (i) CERN/LHCC 96-3;

(ii) E.H.M. Heijne et al.,

“Construction and

characterisation ofa 117 cm?

silicon pixel detector’, IEEE

Trans. Nucl. Sci. NS-42 (1995)

413

We have developed MHz imaging detectors

which have thousands of sensor cells with

associated intelligent readout chips. Arrays of

these cells (pixels) are used for particle tracking

applications. Current pixel size is 50 mmx

500 mm. Several pixel detector arrays, containing

a total of approximately 500 000 pixels, have

been successfully used in the WA97 experiment.

A new pixel readout cell incorporating

improvements that make it more suitable for

| applications in the LHC experiments has been

developed. Silicon pixel assemblies, complete

with readout, have also been used as the anode

plane in an image intensifier. In conjunction with

GaAs sensor matrices a better sensitivity for X-

rays in the 20-60 keV range has been achieved.

Subject: Radiation-hard

microelectronics readout

technology

Collaborators: University of Cracow (PL),

Thomson-TCS (FR), LETI,

Grenoble (FR), RD9

Collaboration, RD29

Collaboration

Contacts: E. Heijne & P. Jarron/

CERN-ECP

(i) CERN/DRDC 94-31;

(ü) P. Aspell et al., ‘Study of

radiation-hard SOI-CMOS

technology for mixed analog-

References:

digital IC design for applications

in LHC’, Proc. Ist Workshop on

Electronics for LHC

Experiments, Lisbon, Sept. 11-

15, 1995, CERN/LHCC 95-56;

(iii) W. Dabrowski et al.,

"Experimental results for Bipolar

Devices and Transimpedance

Preamplifier designed in DMILL

technology after a total dose of

1014 n/cm? and 12 Mrad’, Proc.

Ist Workshop on Electronics for

LHC Experiments, Lisbon,

Sept. 11-15, 1995, CERN/

LHCC 95-56

Evaluation of the radiation-hard 1.2 mm CMOS

technology HSOI3-HD and the DMILL 0.8 mm

BiCMOS technology for applications in analog

and mixed-mode detector readout circuits at the

LHC. An 11-bit 2-stage ADC has been designed

to evaluate with realistic circuits the technology’s

performance, its resistance to radiation, and the

accuracy of the circuit-level simulation models.

Demonstrator front-end chips for the ATLAS

silicon central tracker have been developed in

DMILL technology.

Subject: Evaluation of the radiation

hardness of CMOS deep

submicron processes

Collaborators: IMEC (BE), Mietec (BE), SGS

Thomson (IT), University of

Padua (IT)

Contacts: E. Heijne & P. Jarron/

CERN-ECP

Evaluation of the radiation hardness of standard

deep submicron CMOS processes from Mietec

and SGS Thomson, with the aim of

understanding whether these technologies offer

an alternative to the use at LHC of specially

radiation hardened processes.


Subject: Evaluation of the radiation

hardness of BICMOS VLSI

technology

Collaborators: IBM Microelectronics,

Burlington, Vt (US), University

of Padua Dept. of Engineering

(IT) Contact: A. Marchioro/CERN-ECP

Evaluation of the radiation hardness of a standard

submicron BiCMOS technology for potential

application for LHC detector electronics in areas

subject to low to medium levels of radiation.

Subject: Evaluation of advanced CMOS

deep submicron processes for

mixed signal custom integrated

circuits for LHC applications

Collaborators: France-Telecom-CNET,

Grenoble (FR), SGS Thomson,

Crolles (FR)

Contact: P. Jarron/CERN-ECP

A collaboration with France Telecom’s CNET

research centre with the objective of evaluating

the performance of mixed signal circuits for LHC

applications implemented in the advanced

0.5mm and 0.35 mm CMOS processes under

development by SGS Thomson at the Crolles

wafer manufacturing facility.

Subject: Detector signal processing

circuits with serial analog

output

Collaborators: IMEC (BE), Mietec (BE), CAEN

(IT) Contacts: P Jarron, J.C. Santiard &

E. Heijne/CERN-ECP

W Beusch et al., 'GASPLEX, a

low noise analog signal

Reference:

processor for readout of gaseous

detectors’, CERN-ECP/94-17

(1994)

A family of integrated circuits (AMPLEX1.5,

GASPLEX and GASSIPLEX) have been

developed for readout of various types of

detectors. The programmable VME readout

module CRAMS can be used in conjunction with

these chips. The GASSIPLEX circuit has been

optimized for cathode strip, gas detectors and gas

pad chambers. The noise is 580 r.m.s. e” for a

peaking time of 500. ns and the noise slope is

15 e’/pF. A new chip (DIGIPLEX) that integrates

the GASSIPLEX analog functions with an ADC

and custom logic for pedestal subtraction and

zero suppression is under development.

Health Physics

Subject: Control of spectrometry and

neutron dosimetry in complex

radiation fields

Collaborator: Office federal de l’Energie (CH)

Contact: M. HöferVCERN-TIS

Reference: K 221/TIS

Subject: Measurement of dose equivalent

in relativistic stray radiation

fields

Collaborator: Commission ofthe European

Communities (EU)

Contact: M. Höfer /UCERN-TIS

Reference: Contract F13P-CT92-0026

Instrumentation

Subject: Beam diagnostic devices for the

UNK Project

Collaborator: IHEP, Protvino (RU)

Contact: H. KozioVCERN-PS

Since the beginning of the collaboration in 1992,

13 experts from IHEP have come to CERN to

benefit from CERN’s expertise and facilities.

Development of a closed-orbit observation

system for the upgrade of the 70 GeV

synchrotron (U70) was completed in 1993, and

all instruments and components for manufacture

at IHEP were shipped by the end of 1994.


Development of a closed-orbit measurement

system for the 600 GeV synchrotron (UNKI or

U600) was concluded with successful tests of the

final prototype, on the SPS, with beam, in

November 1994. Further subjects, for both

U70 and U600, were a Q-measurement, a wall-

current monitor and a dc beam transformer.

Owing to the delays affecting the UNK project,

and reorientation of IHEP’s efforts towards U70,

technical activities were interrupted during 1995.

Superconducting Magnets

Subject: Current tests on NbTi wires

Collaborator: Inst. für Experimentalphysik,

Tech. Univ. Vienna (AT)

Contact: L. OberlVUCERN-AT

Reference: Agreement No. L I68/LHC-AT

Measure the critical current and the

magnetization between 4.2 K and 2 K in order to

qualify the production of superconducting NbTi

wires supplied by various European firms

engaged in the R&D work for the LHC

superconducting cables.

Subject: Measurement of materials at 4.2

and 1.8 K

Collaborator: University of Saragossa (ES)

Contact: N. SiegeUCERN-AT

Measurement of material samples, including

magnetic characteristics of steels, at liquid

helium temperature.

Subject: Design and construction of

1.3 m long 6 56 mm dipole

model for very high field

Collaborators: Helsinki Technical Univ. (FI),

Uppsala University (SE) &

Finnish and Swedish Industry

Contacts: D. Leroy & R. Perin/CERN-AT

References: Collaboration agreement;

M. Savelainen, MDISC iron

circuit, Internal note AT/MA

93-85;

CERN AT/93-38 (MA), LHC

Note 247

Design, with a team of four Finnish engineers and

technicians and of one Swedish engineer at

CERN for two years, of a high field

superconducting dipole model for the LHC. The

coil is wound at CERN while the mechanical

pieces are made in Finnish and Swedish industry.

Subject: Collaboration agreement on

superconducting magnets for

the LHC

Collaborator: INFN (IT)

Contact: R. Perin/CERN-AT

Reference: Agreement No. K 23 1/AT

(a) Development, construction and test of a

prototype (-15 m long) superconducting twin

dipole according to the updated CERN LHC

design; (b) measurements of critical currents of

wires and cables for dipoles and other

superconducting magnets; and (c) study, design,

construction and test of a short model (1-1.3 m

long) of a high gradient and large aperture

quadrupole, wound with Nb3Sn conductor.

Subject: Development of a prototype

dipole corrector magnet MBI

Collaborator: Danfysik A/S (DK)

Contact: A. Ijspeer/AT-MA

Reference Agreement No. K 33 7/LHC/AT

Common development work of a MBl corrector

magnet with 1 Tm dipole field operating at

600 A. The collaboration includes mechanical

design, development of prototype winding and

moulding techniques, manufacture of the magnet,

and cryogenic testing at 4.2 and 1.8 K.


Superconducting RF

Subject: Superconducting cavities

Collaborator: INFN, Legnaro (IT)

Contact: E. ChiaverVUCERN-SL

Reference: Agreement No. K 141/AC

Common development of technology for all-

niobium superconducting cavities.

Vacuum

Subject: Vacuum system design

Collaborator: NIKHEF (NL)

Contact: A.G. Mathewson/CERN-LHC

Collaboration to design and provide all the

drawings for the construction of an experiment to

be installed on the dedicated synchrotron

radiation beam line on the CERN Electron

Positron Accumulator (EPA). This experiment

will reproduce as closely as possible the

conditions of the cold vacuum of the LHC and

quantify the behaviour of the LHC cold vacuum

system with synchrotron radiation of the same

critical energy as in the LHC at 7.0 TeV.

Subject: Gas desorption studies

Collaborator: LURE, Orsay (FR)

Contact: A. Mathewson/CERN-LHC

Collaboration to investigate synchrotron radiation

induced gas desorption from vacuum chambers at

ambient temperature. The experiment is installed

on a dedicated synchrotron radiation beam line

on the positron storage ring DCI at LURE.


Collaborator: Lawrence Berkeley Laboratory

(US) Contact: A. Mathewson/CERN-LHC

Collaboration for synchrotron radiation induced

gas desorption studies and the design of the LHC

vacuum system.


Collaborator: Budker Institute for Nuclear

Physics (BINP), Novosibirsk

(RU) Contact: A. Mathewson/CERN-LHC

Collaboration to measure synchrotron radiation

induced gas desorption from vacuum chambers at

4.2 K and 77 K. This experiment is installed on a

dedicated synchrotron radiation beam line on the

VEPP IIM storage ring.


Seminars & Colloquia”

* Unpublished

AC Seminars

Colloquium in honour of Dr G. Brianti on the

occasion of his retirement

K. Hübner, C. Bovet, B. de Raad and L. Evans

(CERN) (950412)

Colloquium in honour of G. Plass on the occasion

of his retirement

G. Munday, H. Haseroth and E. Picasso (CERN)

(950524)

Comparison of the physics potential of lepton and

hadron colliders

P. Darriulat (CERN) (950608)

Superconductors and magnets: part 1

M. Wilson (CERN) (950831)

Superconductors and magnets: part 2

M. Wilson (CERN) (951019)

The European Spallation Source (ESS) - A next

generation neutron source for condensed matter

studies

H. Lengeler (CERN & ESS, KFA Jülich)

(951116)

Astrophysics Seminars

‘Gamma-ray bursts:

Twinkle brightly, gamma star

For still we know not what you are’

R. Wijers (Institute of Astronomy, University of

Cambridge) (950216)

Cosmological implications of light neutrinos:

cold + hot dark matter and large scale structure

J.R. Primack (University of California, Santa

Cruz) (950310)

Solar neutrino problem

V Berezinsky (INFN, Gran Sasso & Institute for

Nuclear Research, Moscow) (950413)

NOT as a supernova: how most stars die

H. Habing (Leiden University) (950523)

X-ray and gamma-ray radiation from active

galactic nuclei and the cosmic background

A. Zdziarski (N. Copernicus Astronomical Center,

Warsaw)

The density of the Universe

M. Rowan-Robinson (Queen Mary College,

London) (950720)

Gravitational lensing of faint galaxies: a practical

probe of cosmology and dark matter

R. Ellis (Institute of Astronomy, University of

Cambridge) (950817)

Neutron stars as clocks — general relativity,

planets and superfluids

A. Lyne (University of Manchester) (950919)

The galactic nucleus

R. Genzel (Max-Planck-Institut für

Extraterrestrische Physik, Garching) (951123)

Elements and isotopes at high redshifts

R.F. Carswell (Institute of Astronomy, University

of Cambridge) (951207)

Seminars & Colloquia

AT Seminars

Recent progress in the development of numerical

field computations

K.R. Richter (Institut für Grundlagen und Theorie

der Elektrotechnik (IGTE) der Technischen

Universität Graz) (950407)

Recent developments in magnetron sputtering

systems

R.D. Arnell (Research Institute for Design,

Manufacture and Marketing, University of

Salford) (950803)

CAS Seminars

What are accelerators good for in everyday life?

G. Brianti (CERN) (950209)

Light- and heavy-ion acceleration at CERN.

The Eleventh Lecture in the John Adams’

Memorial Lecture Series

H. Haseroth (CERN) (951122)

Colloquia

Hubble space telescope images: from collisions

with Jupiter to ancient clusters of galaxies

A. Kinney (Space Telescope Science Institute,

Baltimore) (950209)

The formation of structure in the Universe

G. Efstathion (University of Oxford) (950309)

Early development of neutron scattering

C.G. Shull (Nobel Laureate in Physics 1994,

MIT) (950427)

The discovery of the deformed superheavy

elements 107 to 111

P. Armbruster (GSI, Darmstadt) (950504)

Climate variability and climate change

K. Hasselmann (Max-Planck-Institut für

Meteorologie, Hamburg) (950713)

The use of heavy charged particles in the

radiation therapy of tumors

G. Kraft (GSI, Darmstadt) (951012)

Reflections on the discovery of the T lepton

M. Perl (Nobel Laureate in Physics 1995, SLAC)

(951218)

Computing Colloquia

Optoelectronics |

V Graf (IBM Rueschlikon Lab.) (950127)

Creating the American National Information

Infrastructure — The interaction of science,

technology, business, legislation and politics

R.E. Kahn (President, Corporation for National

Research Initiatives, Washington, DC) (950324)

High level languages as programmer productivity

tools

T. Christiansen (PERL Consultant) (950405)

High performance computing — approaching the

21st century

E.A. Masi (General Manager, Intel Scalable

Systems Division) (950504)

How the Enigma cipher machine was solved

R.E Churchhouse (University of Cardiff, retired)

(950613)

Performance trends in high-end processors

G.A. Sai-Halasz (IBM, T.J. Watson Research

Center, Yorktown Heights, N.Y.) (950724)

The future of Internet

J. Clark (Netscape Communications Corp.)

(951006)


Unifying the Booch and OMT OO development

methods — introduction to the unified method

J. Rumbaugh (Rational Software Corporation)

(951110)

The evolution of the Swiss telecom regulations

P. Fischer (Deputy Director of the Swiss Federal

Office for Telecoms Regulations) (951124)

Computing Seminars

Entering Spaceland

J.-F. Balaguer and E. Gobetti (CRS4, Sardinia)

(950207)

Future Internet protocols

B. Segal (CERN) (950215)

Installation and use of an MPP, the Meiko CS-2

P. Calafıura, R. Hauser and B. Panzer (CERN)

(950301)

GOLEM, a language (and a program) for writing

(and checking) mathematical proofs

E. Remiddi (University of Bologna) (950315)

Track-Parallel GEANT: from dream to reality

M. Guanziroli, C. Casari and G. Meola

(European Architectures Project, CRS4, Sardinia)

(950324)

Central data recording for HERA experiments

using a distributed hierarchical mass storage

system

M. Ernst (DESY) (950426)

P-CAD version 8 update

G. Schnell (Connexe SA, Meyrin), N. Boudot

(Accel. Technologies, Paris) and J.-M. Sainson

(CERN) (950609)

Reusable documents: preparing for the LHC era

M. Goossens and J. Saarela (CERN) (950628)

Status and prospects for HPCN in the USA

P Messina (Caltech) (950913)

Highlights from CHEP ’95

J. Bunn and F. Hassine (CERN) (951004)

Putting software documentation on the Web:

application of LIGHT to the Julia

reconstruction program of ALEPH

M. Aimar and B. Rousseau (CERN) (951108)

Object-Oriented programming with Ada 95

$. Barbey (Software Engineering Laboratory,

EPFL) (951115)

Parallel programs on the CERN SP-2

J. Apostolakis (CERN) (951122)

ROOT: an object-oriented framework for large-

scale data analysis

R. Brun (CERN) (951129)

MCFast - a fast Monte Carlo for detector design

studies

L. Garren (Fermilab) (951206)

Exchange of detector models between GEANT 3

and CAD systems

J. Vuoskoski (CERN) (951213)

Detector Seminars

Digital readout signal processing

$.J. Inkinen (CERN) (950227)

Will micro-strip gas chambers survive the LHC?

C. Garabatos (CERN) (950306)

VMEbus extensions for physics

C. Parkman (CERN) (950313)


The Neutrino Oscillation Search Proposal —

M.IN.O.S.

D.A. Crane (Argonne National Laboratory)

(950327)

Summary of the 7th Vienna Wire Chamber

Conference

C. D’Ambrosio (CERN) (950410)

Radiation hardness study of silicon detectors for

the LHC

$5. Bates (CERN) (950522)

Studies of oxides for microelectronics in an

ionizing radiation environment

N. Saks (Naval Research Laboratory,

Washington, DC) (950615)

Coherent Cherenkov radiation of e”e”— pairs and

its application for the measurement of y-beam

polarization

K.A. Ispirian (Yerevan Physics Institute)

(950828)

The Auger Project: detecting cosmic rays with

the ultimate energies

M. Albrow (Fermilab) (951124)

Real-time pulse parameter extraction from a few

samples

V. Buzuloiu (Polytechnic Institute, Bucharest)

(951204)

The multi-gap RPC: a new type of resistive plate

chamber

C. Williams (CERN) (951211)

Isolde Seminars

Production and stability of the new elements 110

and 111

5. Hofman (GSI, Darmstadt) (950126)

Exotic structures at the drip lines

K. Riisager (Aarhus University) (950215)

Very proton-rich nuclei: decay studies of interest

to nuclear physics and astrophysics

E. Roeckl (GSI, Darmstadt) (950426)

Physics with stored, fast heavy ions: electron-ion

interactions

D. Schwalm (Max-Planck-Institut für Kernphysik,

Heidelberg) (950608)

Mass measurement of !00Sn and other exotic

nuclei at GANIL

M. Chartier (GANIL, Caen) (951130)

LHC Technical Seminars

Electromagnetic design and optimization of

superconducting LHC magnets

5. Russenschuck (CERN) (951026)

LHC machine - radiation doses and radiation

damage

H. Schönbacher (CERN) (951123)

Meetings on Particle Physics Phenomenology

Spin crisis, U(1) problem, and QCD topology

G. Veneziano (CERN) (950120)

Photon colliders: physical program

I.E Ginzburg (ENSLAPP & Institute of

Mathematics, Novosibirsk) (950127)

QOCD scaling violation at small x

K. Ellis (CERN & Fermilab) (950210)

Gauge-invariant anomalous gauge boson

couplings in the Standard Model

J. Papavassiliou (New York University) (950217)


Hadronic contributions to the effective fine

structure constant o{M2) and to g-2 of the

leptons

F. Jegerlehner (PSIT, Villigen) (950224)

Low-x structure functions: high-energy

factorization and next-to-leading corrections

5. Catani (Florence) (950303)

Renormalons and the heavy quark effective

theory

G. Martinelli (CERN & Universitä di Roma ‘La

Sapienza’) (950310)

QCD corrections to the Higgs decays into

massive bottom quarks: methods and results

K.G. Chetyrkin (Institute for Nuclear Research,

Moscow & University of Karlsruhe) (950317)

Gluon fragmentation to aligned charmonia

P. Cho (Caltech) (950324)

Ultra-violet renormalon revisited

A. Vainshtein (Theoretical Physics Institute,

University of Minnesota & Budker Institute of

Nuclear Physics, Novosibirsk) (950327)

Higgs fluxes at LHC

A. Dobrovolskaya (LPTHE, Orsay & ITEP

Moscow) (950407)

Heavy quark production in DIS

F Olness (Southern Methodist University)

(950505)

On the universality of the leading, 1/Q power

corrections in QCD

R. Akhoury (CE, Saclay & University of

Michigan) (950519)

Strange antibaryons from Pb-Pb collisions at

s=(1.8-3.6 TeVJ? J. Rafelski (University of Arizona, Tucson)

(950526)

Real fermionization for superstring model

building

5. Choudhuri (ITP, Santa Barbara) (950602)

QCD sum rules and heavy meson exclusive

decays

A. Khodjamirian (University of Munich &

Yerevan Physics Institute) (950623)

Analytic approach to small-x structure functions

R. Thorne (University of Oxford) (950630)

An update on the light quark masses

D. Wyler (Zürich University) (950721)

Resummation of running coupling effects

in semi-leptonic B meson decays and extraction

oflVy|

P. Ball (CERN) (950728)

Two loop electroweak corrections to the p

parameter, beyond the leading approximation

K. Philippides (New York University) (950804)

All-orders renormalon resummations for some

QCD observables

C. Maxwell (University of Durham) (950811)

Dynamical left-right symmetry breaking

M. Lindner (Technische Universität, Munich)

(950825)

The bermions, an approach to lattice QCD

fermion simulations from negative flavour

numbers

R. Petronzio (Universita di Roma ‘Tor Vergata’)

(950901)

New results from Mueller’s dipole formulation of

small-x physics

G.P. Salam (Cavendish Laboratory, University of

Cambridge) (950908)

Results in strongly-interacting Higgs physics

J.J. Van Der Bij (Freiburg) (950915)


The SM Higgs sector at two loops: when is it

perturbative?

K. Riesselmann (Technische Universität, Munich)

(950922)

Constraints on the B— DIv, D*Iv form factors

I. Caprini (Institute for Atomic Physics,

Bucharest) (950929)

Does unitarity strongly affect the photon-hadron

scattering amplitude?

VA. Petrov (IHEP Protvino) (951006)

Large indirect CP-violation in the neutral kaon

system beyond leading logarithms

U. Nierste (Technische Universität, Munich)

(951020)

Power corrections and renormalons in Drell-Yan

production

V Braun (NORDITA) (951027)

Bloch-Nordsieck thermometers — one-loop

exponentiation in finite temperature QED

D. Indumathi (Dortmund University) (951110)

Minimal supersymmetric standard model Higgs

rates and backgrounds in ATLAS

E. Richter-Was (CERN & Jagellonian University,

Cracow)

Constituent quarks from QCD

M. Lavelle (Univ. Autönoma, Barcelona)

(951201)

Gluon spin in the nucleon

R. Jaffe (MIT, Cambridge, Mass.) (951208)

Unstable particles in gauge theories

A. Pilaftsis (Rutherford Lab., Oxford) (951215)

Particle Physics Seminars

A new light on the Solar neutrinos problem

M. Cribier (DAPNIA/SPP CEN, Saclay)

(950117)

Results on the top search with the DO experiment

at the Tevatron

H.E. Montgomery (Fermilab) (950306)

Probing the gluon at LEP

P. Maettig (University of Bonn) (950307)

Observation of the top quark

B. Winer (University of Rochester) (950314)

Review of electroweak results from EPS-HEP 95

Conference, Brussels

P Wells (CERN) (950829)

Evidence for neutrinos oscillations from muon

decay at rest

H. White (Los Alamos National Laboratory)

(950905)

Review of recent results in B physics from

Lepton-Photon Conference 1995, Beijing

M. Neubert (CERN) (950912)

Neutrino properties and interactions — Review

given at LP-95 Conference, Beijing

K. Winter (CERN) (950926)

Electroweak physics with quarks at DELPHI

K. Moenig (CERN) (951003)

Recent advances in the physics of T decays

M. Davier (LAL, Orsay) (951107)

The RICH detector — generic development and

exploitation for physics

T. Ekelof (Uppsala University) (951114)


Rare B decays: 101 things you can do with

nothing

K. Lingel (SLAC) (951121)

Joint Seminar on First Results from LEP 1.5

L. Rolandi, H. Dijkstra, D. Stickland and

G. Wilson (CERN) (951212)

PPE Seminars

A new method of searching for direct CP

violation: the HyperCP experiment at Fermilab

C. Dukes (University of Virginia) (950116)

Observations of n-B charge-flavour correlations

and resonant Br and BK production

B. Kowalewski (CERN) (950206)

The search for supersymmetry with DO

M. Paterno (University of Rochester) (950313)

Recent QCD results from the DO experiment

J. Yu (University of Rochester) (950327)

Next-to-leading-order QCD analysis of neutrino

charm production by CCFR

A. Bazarko (CERN) (950410)

Measurement of the W mass at CDF

D. Saltzberg (CERN) (950424)

Silicon for lead: use of Si pixels, pads, and strips

for strangeness detection in Pb-Pb collisions

F Antinori (CERN) (950515)

DELPHI luminosity measurement with the new

luminosity monitor

M. Paganoni (Milan University) (950522)

Heavy quark fragmentation and excited beauty

O. Podobrin (University of Karlsruhe) (950612)

Observation of the top quark using a kinematic

technique

M. Cobal (CERN) (950703)

Study of &(2230) in J/y decays and the glueball

interpretation of &(2230)

$. Jin (Institute of High Energy Physics, Beijing)

(950717)

Electroweak measurements from DO

M. Demarteau (Fermilab) (950904)

Measurements of electron capture and stripping

cross-sections for high-energy heavy ions and

their implications |

Y. He (University of California, Berkeley, LBNL)

(950911)

Resultson BB oscillations from ALEPH

O. Schneider (CERN) (951002)

Measurement of CP violation parameters and test

of CPT in the neutral kaon system

M. Dejardin (CEA, DSM, DAPNIA, CE, Saclay)

(951009) |

Single-photon and photon-jet production at DO

B.G. Pope (CERN & Michigan State University)

(951023)

News on the ©2. (ssc)

S. Paul (MPI, Heidelberg) (951030)

Studies of QCD using event shape observables in

e*e” annihilation at the ZP energy

$. Kluth (CERN) (951113)

Recent OPAL results on heavy flavoured hadron

production

A. Martin (Queen Mary and Westfield College,

University of London) (951120)

Results from deep inelastic ep scattering at

HERA

R. Nisius (CERN) (951204)

Measurement of R, =T',5 /Tnad With the

DELPHI detector at LEP

C. Marioti (INFN -Sanita, Rome) (951211)


PS Seminars

The National Centre for Oncological

Hadrontherapy

M. Silari (National Research Council, Milan)

(950118)

The REX-ISOLDE Project

P. Van Duppen (CERN) (950322)

Cooling, recombination and intra-beam scattering

in one computer simulation

C. Teepffer (Erlangen University) (950405)

Development of radio frequency quadrupoles for

argon acceleration

G. Indreas (Institute of Atomic Physics,

Bucharest) (950426)

CRYSTAL: a storage ring for ion beam

crystallization

L. Tecchio (University of Turin) (950614)

Status of the SLAC New Linear Collider Test

Accelerator

R. Ruth (SLAC) (950705)

RHIC machines and its ion sources

K. Prelec (Brookhaven National Laboratory)

(950721)

Commissioning and early operational results

from CEBAF

C. Sinclair (CEBAF, Newport News) (950726)

Towards collisions at the nanometer scale.

Results from the Final Focus Test Beam at SLAC

P. Tenenbaum (SLAC) (950919)

Japan Hadron Project

Y. Mori (INS, Tokyo) (950920)

The magnetron-type varactor: a fast and high

power tuning device for RF cavities

V. Paramonov (Institute for Nuclear Research,

Moscow) (951011)

CLIC, a study for a Compact LInear Collider

J.-P. Delahaye (CERN) (951025)

Science & Society Seminar

Nuclear explosion testing and maintenance of

nuclear weapon stockpiles

R.L. Garwin (IBM) (951009)

Seminars

Search of charmed baryons and narrow baryonia

in the experiment EXCHARM

G. Tatishvili (JINR, Dubna) (950217)

SABER Technology Update Seminar

P. Wilson (European Product Specialist, Analogy

Europe) and Edmund Gerstl (Applications/Sales

Eng., Analogy, Munich) (950509)

Why should the public understand Science?

J. Durant (Professor ofthe Public Understanding

ofScience, Imperial College & Assistant Director

ofthe Science Museum, London) (950726)

Le CERN et son Evolution: les hommes et les

decisions qui ont fait le laboratoire

F. Bonaudi (CERN) (950920)

From the micro- to the macro-cosmos

A. De Rujula (CERN) (951013)

The secrets of colour

D. Travis (System Concepts Ltd.) (951017)

Les applications industrielles de la physique des

particules

O. Barbalat (CERN) (951115)


SL Seminars

Three-turn commissioning of CEBAF

A. Hutton (CEBAF, Newport News) (950120)

Simultaneous, long- and short-lived neutral kaon

beams for experiment NA48

N. Doble (CERN) (950331)

Studies at SLC on a dispersion-free steering

algorithm for future linear colliders

R. Assmann (SLAC) (950512)

An experimental study on the long-term stability

of particle motion in hadron storage rings

W. Fischer (Hamburg University) (950913)

Luminosity and beta function measurement at

LEP

P Castro Garcia (Univ. Valencia & CERN)

(951208) |

Special Colloquium

Present and future programme of KEK

H. Sugawara (Director-General KEK) (950726)

Special Computing Colloquium

The inside story of C++

B. Stroustrup (University of Cambridge)

(950830)

Technical Seminars

The Macrame Project: Realization of a 1000 node

high speed packet switching network

B. Martin (CERN) (950612)

Leakless cooling system

M. Bosteels (CERN) (950619)

Sol-gel optical thin films for an advanced

megajoule class laser ICF-driver

P Belleville and H. Floch (CEA - Centre

d’Etudes de Limeil-Valenton, Villeneuve-Saint-

Georges) (950623)

SAW sensors with wireless read out

F. Seifert (TU, Vienna) (950919)

HEP-PC: A project to explore commodity

computing for HEP

M. Delfino (Univ. Autönoma, Barcelona & SCRI)

(951030)

CHEP95 Trigger & DAQ Session — summary and

comments

$. Cittolin (CERN) (951120)

Report on the First Workshop on Electronics for

LHC Experiments

F. Bourgeois (CERN) (951113)

Multiple target tracking and vertexing algorithms

for HEP

J.-E Pusztaszeri (CERN) (951127)

Mise en &uvre et performance du nouveau

systeme de d&clenchement au niveau 2 de

l’exp£rience L3 utilisant une architecture basde

sur les liens seriels et les ‘routers’ dynamiques

A. Masserot (LAPP, Annecy) (951206)


Theoretical Seminars

Maximal CP violation and subnuclear democracy

H. Fritzsch (University of Munich) (950118)

Non-minimal SUZY breaking, hierarchy and

squark degeneracy

H. Murayama (LBL, Berkeley) (950125)

Non-perturbative symmetries in superstring

theory

M.B. Green (DAMTP Cambridge & CERN)

(950201)

Bethe ansatz for the QCD pomeron

G. Korchemsky (Stony Brook) (950208)

N = 2 supersymmetry and quantum integrable

models

D. Nemeschansky (CERN) (950215)

The age of the Universe

D. Schramm (University of Chicago) (950222)

Phenomenological implications of bottom-T

Yukawa coupling unification

M. Carena (CERN) (950308)

Gauge-invariant effective action for high-energy

scattering in QCD

L. Lipatov (St Petersburg) (950315)

k | -factorization and small-x hard processes

M. Ciafaloni (Florence & CERN) (950322)

Self-interaction correction to black hole radiance

F Wilczek (Institute for Advanced Study,

Princeton) (950329)

Defect mediated electroweak baryogenesis

A.C. Davis (DAMTP, Cambridge & CERN)

(950405)

Soft terms and the flavour problem

5. Dimopoulos (CERN) (950412)

Disoriented and plastic soft terms: a dynamical

solution to the problem of supersymmetric

flavour violations

G. Giudice (CERN) (950426)

Infra-red regularization of superstring theory and

the one-loop calculation of coupling constants

E. Kiritsis (CERN) (950503)

Duality symmetries in string theory

A. Sen (TIFR, Bombay) (950510)

Exact renormalization group flow and BRS

symmetry

G. Marchesini (CERN & Milan University)

(950517)

Phenomenology of light gauginos

G. Farrar (Rutgers University) (950524)

Recent developments in string cosmology

G. Veneziano (CERN) (950531)

Infra-red renormalons and power corrections in

e*e” anihilation into hadronic jets

P. Nason (CERN ) (950614)

Non-minimal Higgs sectors: the decoupling limit

and its phenomenological implications

H.E. Haber (CERN) (950621)

Phenomenology of quarkonia production in

hadronic collisions

M. Mangano (CERN) (950628)

A complete SO(10) SUSY GUT: threshold

corrections

$. Raby (Ohio State University) (950705)

Determining a, at Z: how Nature prompts us

about New Physics

M. Shifman (University of Minnesota) (950712)


Electroweak baryogenesis in supersymmetric

models

P. Huet (University of Washington, Seattle)

(950719)

Cosmic strings, neutrinos and the formation of

high redshift quasars

R. Brandenberger (Brown University,

Providence) (950726)

Second quantization of the Wilson loop

A.A. Migdal (Princeton University) (950802)

Strings, string GUTSs, SUZY-breaking soft terms

L. Ibanez (Univ. Autönoma de Madrid) (950809)

History and story behind Fermat’s last theorem:

200AD - 1994AD

T. Dokshitzer (University of Ütrecht & University

of Lund) (950816)

Physics of micromasers

B. Lautrup (CERN) (950823)

Gaugino condensation, duality and

supersymmetry breaking

F. Quevedo (University of Neuchätel) (950830)

Some recent discoveries with the Hubble space

telescope

J. Bahcall (Institute for Advanced Study,

Princeton) (950908)

An explicit SO(1) x U(1)F model of the Yukawa

interactions

C. Albright (Fermilab) (950913)

Power corrections in QCD hard processes

B. Webber (Cavendish Laboratory, University of

Cambridge) (950920)

Heavy flavour phenomenology from lattice QCD

G. Martinelli (CERN) (950927)

The standard model and beyond in thermal

equilibrium

K. Kajantie (CERN) (951004)

Tests of quark-hadron duality and the running of

a, in T decays

M. Neubert (CERN) (951018)

The strong coupling from lattice QCD

R. Sommer (CERN) (951025)

Weak scale supersymmetry and weak scale —

GUT scale connection

5. Pokorski (MPI, Munich) (951101)

Flipped SU(5) ’95

D. Nanopoulos (CTP, Texas) (951108)

Space, time and colour in hadron production via

ete” > ZU and ete” > WW

K. Geiger (CERN) (951115)

Colour deconfinement and quarkonium

production

H. Satz (University of Bielefeld & CERN)

(951122)

The fractal structure of the Universe

L. Pietronero (Universitä di Roma ‘La Sapienza’)

(951129)

The vacuum structure in the early Universe and

the domain wall, monopole and the cosmological

moduli problems

G. Dvali (CERN) (951206)

V/N expansion for baryons

A. Manohar (University of California, San

Diego) (951213)

Solar neutrinos: on the eve of 1996

A. Smirnov (ICTP Trieste) (951220)


TIS Seminar

Russian-Norwegian Joint Research Projects on

Environmental Radioactive Contamination in

Russia,

a) at dumping sites for nuclear waste in the Kara

Sea,

b) around the nuclear installation ‘Mayak’ in the

Southern Urals

G.C. Christensen (Head of Health and Safety

Department) and T.D. Selnaes (Head of

Department’s Environmental Monitoring Section,

Institute for Energy Technology, Kjeller, Norway)

(950504)


Training Programme 1994/95

(Titles are in the language in which the course/seminar was given)

Academic Training

Lectures for Postgraduate Students

Introduction to quantum field theory

L. Alvarez-Gaume, CERN-TH (4 lectures)

Electroweak interactions

P. Langacker, University of Pennsylvania, USA

(5 lectures)

Quantum chromodynamics

G. Martinelli, CERN-TH (5 lectures)

Beyond the standard model

S5. Dimopoulos, CERN-TH (3 lectures)

Ultimate gradient accelerators: physics and

prospects

A. Skrinsky, INP Novosibirsk, Russia (5 lectures)

Regular Lecture Programme

Detector applications in medicine and biology

A. Del Guerra, University of Ferrara, Italy

(5 lectures)

History of XXth century physics

5. Kapitza, Academy of Sciences, Moscow

(5 lectures)

Fuzzy logic |

P. Smets, Free University of Brussels, Belgium

(5 lectures)

New detector techniques

E. larocci, INFN, Frascati, Italy (5 lectures)

Physics and archaeology

M. Aitken, Oxford University, Oxford, UK

(3 lectures)

Black holes and quantum mechanics

F. Wilczek, Institute for Advanced Study,

Princeton, USA (4 lectures)

B-physics, now and future

T. Nakada, PSI, Villigen, CH (5 lectures)

Issues in the design of LHC

L. Evans, CERN-DG; Y. Baconnier, CERN-AC

(5 lectures)

Observing the very early universe

P. Steinhardt, University of Pennsylvania, USA

(5 lectures)

14 lecture series (64 lectures - 15 lecturers)

Summer Student Lecture Programme

Introductions

An introduction to fundamental concepts of

particle physics (for physics students)

A. de Rüjula (6 lectures)

An introduction to particle physics (for non-

physics students)

E. Lillestgl (4 lectures)


An introduction to CERN

C. Llewellyn Smith (3 lectures)

Courses

Trigger and data acquisition

C. Charpentier (3 lectures)

Current problems in neutrino physics

L. DiLella (5 lectures)

Collider physics

L. Foa (6 lectures)

Particle detectors

H.J. Hilke (6 lectures)

Particle accelerators

J. Jowett (5 lectures)

The Standard Model

R. Kleiss (6 lectures)

Seminars

CP violation

E. Auge (2 lectures)

A cosmology primer

A. Cohen (3 lectures)

The Large Hadron Collider

L. Evans (1 lecture)

Introduction to supersymmetry

5. Dimopoulos (2 lectures)

Neural computing

FE. James (2 lectures)

Computing at CERN

5. Jarp (3 lectures)

Off-line computing from raw data to physics

results

J. Knobloch (3 lectures)

Deep inelastic lepton scattering

M.W. Krasny (2 lectures)

LEAR physics overview / A short overview

R. Landua (1 lecture)

Isolde physics overview

A. Richter (1 lecture)

Heavy ion physics at CERN: from SPS to LHC J. Schukraft (2 lectures)

Other

Student Session:

John Blackburn, Kristian Harder,

Matthias Hillenkamp, Feryal Ozel, Aline Roumy,

Diane Vattolo, Daniel Wagenaar

Average attendance at Summer Student

Lectures: 140 (maximum 235, minimum 70)

Technical Training

Special Technologies

Optique et fibres optiques

Universite St. Etienne, INP Grenoble, ARUFOG

(l session of 5 days)

Optique g&ometrique et physique


(1 session of 2 days)

Fibres optiques et optique integree


(1 session of I day)


Mise en oeuvre et caract£risation des fibres

optiques

ARUFOG (2 sessions of 1 day)

Transmission - composants optiques sources et

detecteurs


(1 session of I day)

El&ments de cryog£nie

CUEFA, Grenoble (1 session of 9 days)

Introduction & la cryog£nie

L. Mazzone (2 sessions of 9 days)

Utilisation et entretien des salles propres

UPS Consultants (2 sessions of 3 days)

Les turbomachines

5. Boudigues (1 session of 4 days)

Techniques de collage

CAST (1 session of 2.5 days)

Systems & Networks

Utiliser UNIX

Osyx (4 sessions of 2 days)

UNIX for end-users

J. Brazier (1 session of 2 days)

UNIX pour programmeurs

Osyx (2 sessions of 5 days)

UNKX for programmers

J. Brazier (2 sessions of 5 days)

LynxOS programming


INIX Systems Administration

Hewlett Packard, Sun Service

(3 sessions of 1.5 days)

KORN shell programming


Reseaux informatiques locaux

Anthonioz-Blanc, Flückiger, Rochez

(1 session of 1.5 days)

Nouvelles fonctionnalites HP-UX 10.0

Hewlett-Packard (1 session of 2 days)

New features of HP-UX 10.0

Hewlett-Packard (1 session of 2 days)

Introduction to software engineering

J. Deacon (1 session of 3 days)

Object oriented analysis and design

J. Deacon (1 session of 4 days)

Electronics Design

LabVIEW

National Instruments (4 sessions of 3 days)

LabVIEW advanced

National Instruments (1 session of 2 days)

CADENCE

Cadence Design System (1 session of 5 days)

Fuzzy logic basics to practical aspects

L. Lemaitre (1 session of 2 days)

Fundamentals of digital signal processing

D. Von Grüningen (1 session of 4 days)

Signal integrity

I. Novak, P. Sayre (1 session of 4 days)

Introduction to VHDL

Bacstreet (1 session of 2 days)

VHDL

Bacstreet (1 session of 5 days)


Materials & Mechanical Design

AutoCAD ler niveau

Afitec (2 sessions of 4 days)

AutoCAD 2&me niveau

Afitec (1 session of4 days)

MathCAD

J. C. Schnuriger (1 session of 2 days)

Proce&des de contröle non destructif

Institut de Soudure (2 sessions of 5 days)

Office Automation & Administrative

Techniques

Permanence bureautique

CIP (16 sessions of I day)

Word ler niveau sur Macintosh

CIP (3 sessions of 2.5 days)

Word ler niveau sur PC

Softpower (1 session of 2.5 days)

Word 2&me niveau sur Macintosh

CIP (1 session of 1.5 days)

FileMaker Pro sur Macintosh


FileMaker Pro sur PC

CIP (I session of 2 days)

Ateliers de FileMaker

CIP (3 sessions of 1 day)

Excel ler niveau sur Macintosh


Excel ler niveau sur PC


Excel 2&me niveau sur Macintosh


Excel 2&me niveau sur PC

Softpower (2 sessions of 2.5 days)

Excel 3&me niveau sur PC

Wang (1 session of 1.5 days)

Introduction au PC


Introduction au Macintosh

ICIP (5 sessions of 1.5 days)

Introduction to Macintosh

ID-Form (1 session of I day)

ACCESS

SF Media (1 session of 2.5 days)

HTML for the World-Wide Web

B. White (1 session of 2 days)

Navigation dans le WWW du CERN

R. Cailliau et al. (8 sessions of half a day)

Navigating the CERN WWW

R. Cailliau et al. (4 sessions of half a day)

Information mapping

B. Palmer (1 session of 2.5 days)

Software Development Tools

Programmation en C

Osyx (1 session of 5 days)

Programming in C


C++ programming

Natsoft (1 session of 4 days)


Oracle forms V4

Oracle (1 session of 5 days)

New technical features on Oracle 7

Oracle (2 sessions of 4 days)

Oracle CASE workshop

Oracle (1 session of 5 days)

Presenting data with Oracle Graphics V2

Oracle (2 sessions of 2 days)

Visual Basic

SF Media, Diademe (3 sessions of 2.5 days)

C, C++, Motif

Computer College (4 sessions of 5 days)

Oracle Reports V2

Oracle UK (1 session of 4 days)

ESA software engineering standards

J. Fairclough (2 sessions of 3 days)

Oracle pour utilisateurs

Oracle (6 sessions of 2.5 days)

PERL 5

T. Christiansen (1 session of 2 days)

Visual C++ and Microsoft Foundation Class

Library

Microprocess (1 session of 5 days)

Management & Communication

Management

Information for supervisors /Information pour

superviseurs

CERN Experts (1 session of 2 days)

Formation & l’appr&ciation des performances

P. Artigues ou F. Labro, CERN

(4 sessions of 2 days)

Performance Appraisal Workshop

R. Phillips, Ashridge Management College


Pratique de la supervision, seminaire de base

P. Artigues, Centor (2 sessions of 2 days)

Supervision in practice, basic seminar

R. Phillips, Ashridge Management College

(] session of 2 days)

Pratique de la supervision, suivi

P. Artigues, Centor (1 session of 2 days)

Supervision in practice, follow-up

P. Hodgson, Ashridge Management College


Workshop on CERN today and tomorrow /Atelier

de reflexion sur le CERN d’aujourd'hui et de

demain

CERN Managers (1 session of 3 days)

Communication

Effective, rapid reading

P Jacobs (2 sessions of 2 days)

Effective, rapid reading — follow-up

P Jacobs (1 session of I day)

Rediger un document administratif

M.-J. Astre-Demoulin, Paroles Sarl

(1 session of 2 days)

Techniques d’expos& et de presentation

I. Chevalier, Centor-Idep (2 sessions of 2 days)

Animer une r&union de travail

I. Chevalier, Centor-Idep (1 session of 2 days)


Running meetings

M. Matthews, CAPP Conseil (I session of 2 days)

Making presentations

S. Allender, Beetik (2 sessions of 2 days)

Making presentations, follow-up:

Using visuals aids

$. Allender, Beetik (2 sessions of I day)

Negotiating skills

D. Cleeton, GBS (3 sessions of 2 days)

Communiquer efficacement, lere partie


Communicating effectively, part 1

$. Datta Cockerill, CERN (2 sessions of 2 days)

Communiquer efficacement, 2&me partie


Communicating effectively, part 2

S. Datta Cockerill, CERN (2 sessions of 2 days)

Les outils de communication dans une Equipe

P. Artigues, Centor (1 session of 2 days)

Language Training

Regular Courses

French

Beginners

(8 courses of 60 hours)

Intermediate


Advanced


English

Beginners


Intermediate


Advanced


Special Courses

French

1 writing course level 2 of 30 hours

1 private course of 25 hours

2 self-paced courses

English

l preparation for exam course of 16 hours

2 writing courses of 24 hours

1 meeting course 24 hours

3 informatics courses

(I of4 hours, I of 24 hours and I of 60 hours)

3 speaking courses

(1 of 28 hours, 2 of 15 hours)

2 English courses (group) of 40 hours

2 self-paced courses


Training Seminars

Training in Marks & Spencer (22.9.1994)

Maryse Hessing, Marks & Spencer, London

The role of self study language training in the

scientific community (15.12.1994)

Daphne Goodfellow, Montpellier

Les arbres de connaissance (2.3.1995)

Pierre Levy, Universite Paris Dauphine

General Education

Talks

Science pour tous

R. Carreras, CERN

A series of 33 talks (in French) intended

primarily for people with no scientific training.

Between 30 and 70 people attended each talk.

Publication

Picked up for you this week

R. Carreras, CERN

A weekly sheet (in English) of press cuttings of

general scientific interest.

About 1500 copies per weekly edition and about

3200 of the complete edition for the year.

Training Organized Directly by the Divisions in 1994/95

Fuller details of this are given on pages 11 and 12

of the statistical supplement to the Report on

training statistics and expenditure in 1994/95, a '

summary being given below. Of the training

organized by the Divisions inside CERN 82%

concerned Technical Training, 10% being

Academic and 8% Management &

Communication Training, while for training

outside CERN the breakdown was 59% Technical

Training, 27% Academic Training, 4%

Management & Communication Training and

10% Language Training.

On-site | Off-site | Total

Technical Training 2546 1374 3920

Academic Training 318 635 953

Management & 254 100 354

Communication

Training

Language Training _ 233 233

Total man-days 3118 2342 5460

Apprenticeships

Number of apprentices from September 1994

to August 1995: 28

Profession ist | 2nd | 3rd | 4th | Total

year | year | year | year

Laborant en 3 2 2 2 9

Physique

Electronicien 4 4 4 4 16

Employe de l 1

commerce Three out of four ‘Electroniciens’, the two

‘Laborants en Physique’ and the ‘Employede de

commerce’ who completed their apprenticeships

in 1995 obtained the Swiss ‘Certificat F&dEral de

Capacite’ (CFC).


CERN Schools

Accelerator School

The CERN Accelerator School normally arranges

two courses in Member States each year. The first

of these is a specialist course which takes place in

the spring and is followed in the autumn by a

course on general accelerator physics at either the

Introductory or Advanced level. Now that the

LHC has been approved and design and

construction is being planned, CAS has decided

to match its specialist courses to the needs of the

project. To start the series off appropriately, the

topic chosen for this year’s course was

‘“Superconductivity in Particle Accelerators’. The

school was organized jointly with DESY at Haus

Rissen, Hamburg, Germany from 17 to 24 May.

In spite of being a repeat of a similar course held

six years ago it attracted 90 participants showing

that interest in this subject is continually

renewed.

Lectures

Superconductivity

P Schmüser, DESY

Fields, forces and mechanics of superconducting

magnets

R. Perin, CERN

Cryogenics

J. Schmid, CERN

Basic properties of superconducting cavities

W. Weingarten, CERN

Impact of superconductors on LHC design

J. Gareyte, CERN

Survey of superconducting materials

M. Wilson, CERN

Superconducting detector magnets

A. Dael, CEA Saclay

Ginsburg-Landau theory

M. Cyrot, CNRS Grenoble

Practical superconductors for magnets

M. Wilson, CERN

Quest for high r.f. field

D. Proch, DESY

Operating HERA with superconducting magnets

F. Willeke, DESY

Superfluidity

W.E Vinen, University of Birmingham

Persistent and eddy currents

A. Devred, CEA Saclay

Field emission for cavities

Materials for cavities

B. Bonin, CEA Saclay

Impact of superconducting cavities on LEP2

design

D. Boussard, CERN

1.8K

P. Lebrun, CERN

CERN Schools

Impact of persistent and eddy currents on

accelerator performance

B. Holzer, DESY

Couplers for cavities

E. Haebel, CERN

Quench protection

K.-H. Mess, DESY

Recirculating linacs

D. Gräf, TH Darmstadt

High-temperature superconductors

G. Müller, Bergische Universität

TESLA

B. Wiik, DESY

This year it would normally have been the turn of

the Advanced Level Accelerator Course but,

finding there had been a dwindling in support for

the Advanced Level, CAS mounted a course at an

Intermediate level. Indeed this proved more

popular and 67 participants attended the school

held at Eger in Hungary from 18 to 29 September.

This was the first time the School has been held

in one of Europe’s eastern countries and was an

appropriate welcome for Hungary as she joins the

family of CERN Member States.

Lectures

Application of accelerators

G. Brianti, CERN

Hamiltonian mechanics

J. Hagel, Madeira University

Longitudinal dynamics

J. Le Duff, LAL

Transverse dynamics

E.J.N. Wilson, CERN

Beam transfer

J. Rossbach, DESY

"Transverse dynamics

P. Schmüser, DESY

Synchrotron radiation

L. Rivkin, PSI

Beam measurements

K. Cornelis, CERN

Non-linear resonances

E.J.N. Wilson, CERN

Coupling

C. Biscari, INFN-LNF

Self fields, Q-shifts, longitudinal space charge

K.-H. Schindl, CERN

Insertions

A. Ropert, ESRF

Instabilities

A. Hofmann, CERN

Linacs

H. Henke, TU Berlin

Cooling I

J. Bosse, CERN

Cooling II

D. Möhl, CERN

Machine development

Machine design

HA. Lengeler, CERN

Space charge, beam transport

C. Prior, RAL

Medical applications

U. Amaldi, CERN

Seminars

Heavy-ion sources

S. Biri, Atomki, Debrecen

CERN Schools

Heavy-ion experiments

G. Vesztergombi, CERN

Scientific presentation

T. Taylor, CERN

Collective and unconventional accelerators

I. Ivanov, JINR

Application of accelerators in industry and solid

state research

I. Meshkov, JINR

Effects of tidal forces on the beam energy

A. Hofmann, CERN

School of Computing

The 1995 CERN School of Computing took place

in Arles, France, from 20 August to 2 September

1995, and brought together 21 lecturers and

68 students from 44 institutes from 17 different

countries, and of 21 different nationalities. The

School was organized in collaboration with the

Institut National de Physique Nucl&aire et de

Physique des Particules (IN2P3) which is part of

the Centre National de Recherche Scientifique,

France.

The main lecture programme was as follows:

Human Computer Interfaces

Computer graphics and human computer

interfaces

J. Gallop, Rutherford Appleton Laborator,,

Didcot, UK

Virtual prototyping at CERN

$S. de Gennaro, CERN

Event display: can we see what we want to see?

H. Drevermann, CERN

Collaborative Software Engineering

The RD13 DAQ system and the object

management workbench

R. Jones, CERN

CICERO RD-38: a distributed information

system for HEP controls

J.-M. Le Goff, CERN

Object oriented programming and high energy

physics

D. Quarrie, Lawrence Berkeley Laboratory,

Berkeley, USA

Applying an object oriented approach to offline

reconstruction at the LHC |

RD Schaffer, Laboratoire de l’Accelerateur

Lineaire (LAL), Orsay, France

Information Super Highways

First driving classes on the information super

highway

W. Bauerfeld, DeTeBerkom, Berlin, Germany

Information highway applications

D.C. De Roure, University of Southampton,

Southampton, UK

Trends in Computer Architecture/ Industry

Brief history of computer architecture evolution

and future trends

R. Groves, IBM Corporation, Austin, Texas, USA

High-speed switching

T. Engbersen, IBM Zürich Research Lab.,

Rüschlikon, Switzerland

Mass data storage: technical improvements and

future trends

C. Maillot, Thomson-CSF, Orsay, France

CERN Schools

Parallel Architectures (MPP)

An introduction to message passing paradigms

D. Walker, Oak Ridge Laboratory, Oak Ridge,

USA

FORTRAN 90-a thumbnail sketch

M. Metcalf, CERN

High-performance FORTRAN

M. Metcalf, CERN

Mathematical Computing

Using a statistics package

R. Barlow, University of Manchester, Manchester,

UK

Three lectures on Mathematica

M. Trott, Wolfram Inc., Champaign, USA

Data Acquisition Systems

Simulation and modelling tools in data

acquisition system design for future high energy

physics experiments

M. Haney, University of Illinois, Urbana, USA

Switching techniques in data acquisition systems

for future experiments

M. Letheren, CERN

World-Wide Web for Physics

World-Wide Web technologies

H. Lie, INRIA-W3, Sophia Antipolis, France

Publishing on the Web

B. Rousseau, CERN

Interfacing to the Web

M. Dönszelmann, CERN

1995 European School of High- Energy Physics

The 1995 European School of High-Energy

Physics was organized in Dubna, Russia from

27 August to 9 September. The 1995 School was

attended by 87 students, 68 and 16 from CERN

and JINR Member States, respectively, and three

from non-member states. The main lecture

courses, designed to give young experimental

high-energy physics doctoral students a sound

basis in theory, were as follows:

Field theory

Prof. E. Verlinde, CERN

The Standard Model

Prof. B. Arbusov, IHEP, Protvino

Beyond the Standard Model

Prof. G. Guidice, CERN

QCD and deep inelastic scattering

Yu. Dokshitzer, Lund/St.Petersburg NPI

B-physics and CP violation

Prof. M. Neubert, CERN

Dark Matter

Prof. M. Spiro, Saclay

Neutrino oscillations

Prof. L. Di Lella, CERN

Experimental technique

Prof. D. Fournier, Orsay

A number of more specialized lectures were also

given, including reviews of the physics

programmes of CERN and JINR. In total,

32 lectures, each of 90 minutes duration were

given.

The lectures were reinforced by discussion

sessions, also of 90 minutes duration, held most

days during the school. Each discussion group of

about 20 students was guided by a discussion

leader.

CERN Schools

Distinguished Visitors in 1995

January

26 Mr Shimon Peres

Foreign Minister, Israel (5)"

26 Professor Vladimir Dvorak

Director of the Institute of Physics, Acadamy

of Sciences, Czech Republic (1)

February

8 Mrs Colette Lewiner

President and Chief Executive Officer,

SGN-Eurysis, France (4)

March

8 Mr David HuntM.P.

Chancellor of the Duchy of Lancaster

Minister for Public Service and Science,

United Kingdom (6)

9 Professor George Efstathiou

Head of Astrophysics, Department of

Physics, University of Oxford, United

Kingdom (1)

10 Professor Graham Farquhar

Professor of Biology, Research School of

Biological Sciences, Australian National

University (1)

* No. of visitors.

17

24

24

24

25

28

29

His Excellency Mr Bjern Skogmo

Ambassador, Permanent Representative of

Norway to the United Nations and other

International Organizations in Geneva (1)

VAMAS Group, International

Organization for Standardization (Versailles

Project on Advanced Materials and

Standards) (18)

Dr Boris Saltykov

Minister of Science, Advanced Education

and Technological Policy, Russian

Federation (2)

Professor Robert Kahn

President of the Corporation for National

Research Initiatives, United States of

America (1)

Board of Regents of the University of

Nijmegen, Netherlands (12)

The Parliamentary Office for the Assessment

of Scientific and Technological Choices,

France (10)

Mr Pham Chänh Truc

Vice-President of the People’s Committee of

Ho Chi Minh City, Vietnam (5)


April

3

20

27

Mr Doru Dimitru Palade

Minister of Research and Technology,

Romania (5)

Professor W. Harris

Member of the Directorate, National Science

Foundation, United States of America (1)

His Excellency Mr Oscar Luigi Scalfaro

President of Italy (9)

Professor Clifford Shull

M.1.T., Cambridge, United States of

America. 1994 Nobel Prize for Physics (1)

May

18

19

19

22

24

Dr Catherine Cesarsky

Director, Directorate of the Sciences of

Matter, Saclay, France (3)

. Mr Jeröme Koechlin

Head of Protocol, Republic and Canton of

Geneva (1)

Dr Y. Gleitman

Chief Scientist, Ministry of Industry,

Israel (3) |

Dutch Consuls in Switzerland (24)

Physics Action Council / UNESCO

meeting (10)

Mr James Verity

National Audit Office, United Kingdom (3)

Dr Jean-Marie Luton

Director-General, European Space Agency

(ESA) (1)

June

1

15

16

16

23

Ms S. Aloni

Minister of Telecommunications and of

Science and the Arts, Israel (14)

Professor Peide Weng

Deputy, Institute of Plasma Physics, Chinese

Academy of Sciences, People’s Republic of

China (3)

Visit of the Consular Corps of Geneva (13)

Mr Habib A.A. Shaheen, Saudi Arabia

Mrs Nicola K. Furey, Belize

Mrs Liliane Alvarado Overviek, El Salvador

Mr. Barcia Garcia-V., Spain

Mr Teferi Melesse Desta, Ethiopia

Mrs Eleanor Baha, United Kingdom

Mr Victor Haesen, The Netherlands

Mr Augusto Martins Gongalves Pedro,

Portugal

Mr Zaid M. Hajar, Yemen

Professor Wiranto Arismunandar

Rector, Technical Institute of Bogor (ITB),

Indonesia (16)

Mr Rishpaul Singh

Consulate General, Permanent Mission of

India in Geneva (2)

Mr Kaoru Yosano

Minister of Education, Science and Culture,

Japan (8)


July

5 Professor Verena Meyer

President, Swiss Science Council, University

of Zurich, Switzerland (3)

13 Professor Hans Zacher

President, Max-Planck-Gesellschaft,

Munich, Germany (1)

26 Mir Bernard Pelların

President, General Council of Haute-Savoie,

France (15)

27 Professor J. Nüech

President, Swiss Federal Institute of

Technology Zurich (ETH), Switzerland (1)

August

3 Mr Paul Ignatieff

Director of Unicef (1)

September

1 JETRO, Japan External Trade

Organization (17)

4 His Excellency Mr Munir Akram


Pakistan to the United Nations and other


5 Commission for the Management of the

Swiss National Scientific Research Fund (18)

11 His Excellency Mr Walter Gyger

Permanent Observer of Switzerland to the

Office of the United Nations and Permanent

Representative of Switzerland to the


19 Mr Koga

Director, Japan External Trade Organization

(JETRO), Geneva (4)

29 Dr Elisabeth Dufourcgq

Secretary of State for Research, France (4)

October

16

23

Professor Minoru Oda

President, Tokyo University of Information

Sciences, Director, International Institute for

Advanced Studies, and Member, Japan

Academy (1)

Mr Riccardo Lombardo

President, ANTEL Telecommunications,

Uruguay (5)

Representative Sherwood Boehlert and

Representative Vernon J. Ehlers

Members of the Science Committee,

United States Congress (3)

Mr G.P. Lockton

H.M. Consul-General, British Consulate-

General, Lyon (2)

Mr Hiroshi Matsui

Director, Office of Operational Safety and

Administration, Tokai Research Institute,

Japan Atomic Energy Research Institute

(JAERI) (15)

Dr R.J. van Duinen

President, Organization of Scientific

Research (NWO), Netherlands (2)

Mr Adolf Ogi

Federal Councillor, Federal Department of

Transport, Communications and Energy,

Berne, Switzerland (4)


23 Mr Miroslav Somol

Vice-Minister for Industry and Trade,

Czech Republic (3)

24 Mr Robert Barnett

25

Science and Technology Counsellor to

Switzerland, British Consulate-General,

Bonn (1)

‘PRIDE’, Norwegian Industrialists (25)

November

A

7

7

9

13

17

21

Confederation of Conferences of European

Rectors (37)

Dr Christian Hambro

Director-General, Norwegian Research

Council (1)

Dr H. Brinkman

Vice-Chancellor, Vrije Universiteit

Amsterdam, Netherlands (3)

Mrs Damilleville

Head, Office of the Ministries of the Civil

Research and Development Budget,

Financial Affairs Service — Directorate of

Research Administration and Finance,

Ministry of Higher Education and Research,

France (1)

Professor Herbert Mang

Secretary-General, Academy of Science,

Austria (3)

His Excellency Mr Daniel Bernard


France to the United Nations Office and

Specialized Institutions based in Geneva (4)

The Committee on Science and Technology

of the Parliamentary Assembly of the

Council of Europe (30)

23

28

28

Professor Bedrich Sedläk

Dean of the Faculty of Mathematics and

Physics, Charles University, Prague,

Czech Republic (4)

Maitre Maurice Aubert, legal mediator,

Vice-President of the International

Committee of the Red Cross, Geneva,

Switzerland (12)

Professor Aleksander Luczak

Deputy Prime Minister, Chairman of the

State Committee of Scientific Research,

Poland (14)

December

5

14

Professor V.A. Belugin

Director-General, Arzamas,

Russian Federation (4)

Asıan Pacific Ambassadors in Berne (7)

His Excellency Mr Yasushi Kurokochi, Japan

His Excellency Mr Zia Ispahani, Pakistan

His Excellency Mr Machmud Subarkah,

Indonesia

His Excellency Mr Kizhakke Pisharath

- Balakrishnan, India

18

His Excellency Mr Don Pramudwinai,

Thailand

His Excellency Mr Hay Son Kim, South

Korea

His Excellency Mr Tomas T. Syquia,

The Philippines

Mr John R. Nichols

H.M. Consul-General, British

Consulate-General, Geneva (1)


Report of Activities - CERN Document Server

Documents

Transcript of Report of Activities - CERN Document Server