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CERN 99-05 19 August 1999 XCO1F234O ORGANISATION EUROPEENNE POUR LA RECHERCHE NUCLEAIRE CERN EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH CERN ACCELERATOR SCHOOL VACUUM TECHNOLOGY Scanticon Conference Centre, Snekersten, Denmark 28 May-3 June 1999 PROCEEDINGS Editor: S. Turner 1999 © Copyright CERN, Genève, 1999 Propriété littéraire et scientifique réservée pour Literary and scientific copyrights reserved in all tous les pays du monde. Ce document ne peut countries of the world. This report, or any part être reproduit ou traduit en tout ou en partie sans of it, may not be reprinted or translated without l'autorisation écrite du Directeur général du written permission of the copyright holder, the CERN, titulaire du droit d'auteur. Dans les cas Director-General of CERN. However, appropriés, et s'il s'agit d'utiliser le document à permission will be freely granted for appropriate des fins non commerciales, cette autorisation non-commercial use. sera volontiers accordée. If any patentable invention or registrable design Le CERN ne revendique pas la propriété des is described in the report, CERN makes no inventions brevetables et dessins ou modèles claim to property rights in it but offers it for the susceptibles de dépôt qui pourraient être décrits free use of research institutions, manufacturers dans le présent document ; ceux-ci peuvent être and others. CERN, however, may oppose any librement utilisés par les instituts de recherche, attempt by a user to claim any proprietary or les industriels et autres intéressés. Cependant, le patent rights in such inventions or designs as CERN se réserve le droit de s'opposer à toute may be described in the present document. revendication qu'un usager pourrait faire de la propriété scientifique ou industrielle de toute invention et tout dessin ou modèle décrits dans le présent document. ISSN 0007-8328 ISBN 92-9083-149-9 PLEASE BE AWARE THAT ALL OF THE MISSING PAGES IN THIS DOCUMENT WERE ORIGINALLY BLANK CERN 99-05 KS002511593""""'"""""''""'"" "/H"""" 19 August 1999 R: KS DEO13511199 XCO1F234O ORGANISATION EUROPEENNE POUR LA RECHERCHE NUCLEAIRE CERN EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH CERN ACCELERATOR SCHOOL VACUUM TECHNOLOGY Scanticon Conference Centre, Snekersten, Denmark 28 May-3 June 1999 PROCEEDINGS Editors: S. Turner GENEVA 1999 CERN-Service ^information scientifique-RD/993-1800-aout 1999 Ill *DEO13 :: ABSTRACT These proceedings present the lectures given at the twelfth specialized course organized by the CERN Accelerator School (CAS), the topic this time being 'Vacuum Technology'. Despite the importance of vacuum technology in the design and operation of particle accelerators at CERN and at the many other accelerators already installed around the world, this was the first time that CAS has organized a course devoted entirely to this topic. Perhaps this reflects the facts that vacuum has become one of the more critical aspects of future accelerators, and that many of the pioneers in the accelerator field are being replaced by new, younger personnel. The lectures start with the basic concepts of the physics and technology of vacuum followed by detailed descriptions of the many different types of gas-pumping devices and methods to measure the pressures achieved. The outgassing characteristics of the different materials used in the construction of vacuum systems and the optimisation of cleaning methods to reduce this outgassing are then explained together with the effects of the residual gases on the particle beams. Then follow chapters on leak detection, materials and vacuum system engineering. Finally, seminars are presented on designing vacuum systems, the history of vacuum devices, the LHC (large hadron collider) vacuum system, vacuum systems for electron storage rings, and quality assurance for vacuum. I Niels Bohr Institute CERN Accelerator School course on Vacuum Technology Scanticon Conference Centre ; Borupgaard, Copenhagen, Denmark | :,-.• 28 May-3 June 1999 For students and staff in laboratories, universities and manufacturers of particle accelerators and other large vacuum systems. information, scholarship and application forms from; CERN Accelerator School E-mail: Su*anne.vonAVartburg©cerrt.Ch CH-1211 Geneva 23 Web: http-7/www.cern.ch/Schools/CAS/ Switzerland Fax: +4122 767 54^0 Sponsors: fl*j QANFYSIK VACUUM TECHNOLOGY Scanticon Borupgaard Conference Centre, 28 May - 3 June 1999 Friday Saturday Sunday Monday Tuesday Time Wednesday Thursday 28 May 29 May 30 May 31 May 1 June 2 June 3 June BREAKFAST 09.00 Introduction to Outgassing I Outgassing II Outgassing III Engineering Leak detection vacuum physics (physics) (static (dynamic II outgassing) outgassing) 10.00 N. Marquardt J. de Segovia K. Jousten O. Grobner L. Westerberg N. Hilleret COFFEE E BREAK 10.10 Pumps I Materials Cleaning I Engineering I Vacuum Extreme high (mechanical) controls and vacuum V X operation 11.10 N. Hilleret E. Huttel R. Reid L. Westerberg D. Schmied P. Redhead LUNCH c • COFFEE 11.30 Pressure Pumps II Pumps III Pumps IV Beam "The best laid measurement I (ion-pumps) (getters) u (cryo-pumps) residual gas schemes..." (total) interactions I (lifetime effects) R 12.30 Ch. Edelmann L Schulz C. Benvenuti C. Benvenuti S. Pape L. Westerberg M0ller TEA S LUNCH;. 14.30 Seminar Pressure Pressure Cleaning II Beam Designing Measurement Measurement T residual gas Accelerator II III interactions II vacuum systems (ionisation (partial (neutralisatio gauges) pressure) o effects) 15.30 P. Marin K. Jousten J.H. Leek R. Reid A. Poncet Welcome Reception N TEA ,. 16.00 Seminar Seminar Seminar Seminar History LHC Vacuum Quality of vacuum Vacuum * system Assurance devices system for electron for vacuum storage rings 17.00 P. Redhead O. Grobner D. Kraemer R. Reid 20.00 EVENING MEAL BANQUET MEAL Participants and setting of the Vacuum Technology course at Snekersten, Denmark, 1999 Vll FOREWORD The aim of the CERN Accelerator School to collect, preserve and disseminate the knowledge accumulated in the world's accelerator laboratories applies not only to accelerators and storage rings, but also to their related sub-systems, equipment and technologies. This wider aim is being achieved by means of the specialized courses listed in the Table below. The latest of these was on the topic of Vacuum Technology, held at the Scanticon Conference Centre, Snekersten, Denmark, from 28 May to 3 June 1999, its proceedings forming the present volume. Over the last few years vacuum technology has made great strides forward and has become of immeasurable importance. Industry currently uses ultra-high vacuum in many production processes while the more recently achievable extreme high vacuum is necessary for the simulation of interstellar space and in the processing of sophisticated semiconductor devices, and particularly in the field of particle accelerators and storage rings. Therefore it was felt to be the appropriate moment to design a course where the many facets of technology required to produce and measure the different degrees of vacuum could be brought together into a logical sequence. Naturally, with so much progress having been made in the accelerator field, it was clear that accelerator rerquirements should form the backbone of the course especially since the techniques used there are applicable in most other research institutes and in industry. The resulting series of lectures and seminars was presented at the course and written-up for the use of the present and future workers in this discipline. Organization of this course and the production of its proceedings relied very heavily on the help and encouragement CAS received from many Institutes, Companies and individuals. In particular we wish to acknowledge the help of J.D. Hansen and H. Vedel of the Niels Bohr Institute, K.N. Henrichsen of CERN as well as Director Prof. Ove Poulsen for his lively and provocative opening talk. Financial support in the form of scholarships from UNESCO, NORFA, SNF/HEP and Danfysik was also most appreciated along with the generous budget made available by the CERN Management. The CAS Advisory, Programme and Local Organizing Committees also deserve sincere thanks for the guidance and attention to detail that ensured the great success of this course. The efficient and friendly service provided by the staff of the Scanticon Conference Centre made our stay there most enjoyable as well as educative. However the greatest effort was made by the course lecturers in preparing and presenting the various topics as well as writing the chapters of these proceedings. Not only the participants at the course but also all those who will use these proceedings in the future owe them a great mark of gratitude. Last, but certainly not least, the attendance and keenness of the participants from so many parts of the world made the efforts made for them so worthwhile and we thank them most warmly. S. Turner Editor Vlll LIST OF SPECIALISED CAS COURSES AND THEIR PROCEEDINGS Year Course Proceedings 1983 Antiprotons for colliding beam facilities CERN 84-15 (1984) 1986 Applied Geodesy for particle accelerators CERN 87-01 (1987) also Lecture Notes in Earth Sciences 12, (Springer Verlag, 1987) 1988 Superconductivity in particle accelerators CERN 89-04 (1989) 1989 Synchrotron radiation and free-electron lasers CERN 90-03 (1990) 1990 Power converters for particle accelerators CERN 90-07 (1990) 1991 RF engineering for particle accelerators CERN 92-03 (1992) 1992 Magnetic measurement and alignment CERN 92-05 (1992) 1993 RF engineering for particle accelerators - (repeat of the 1991
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