DOCSLIB.ORG

Cern Accelerator School Vacuum Technology

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Cern Accelerator School Vacuum Technology 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
Load more

Recommended publications
  • Vacuum – Nothing but Pressure
    By Mike Tuohey, Sales & Marketing Communications Manager, Piab USA Inc. Vacuum – nothing but pressure According to the dictionary, vacuum is a space completely empty of substance. Yet, in engineering, vacuum is employed for a number of tasks. So, how can nothing be utilized to do something? Well, without pressure it wouldn’t work. Vacuum is an ideal and elusive state, and from a practical point of view it is perhaps not necessary to use this theoretical term, once a hot topic among philosophers in ancient Greece, especially since most modern thinkers agree that a complete or perfect vacuum does not exist. Even if all matter could be removed from a volume, it would still not be empty due to dark energy, rays, neutrinos and other phenomena in quantum physics. However, in particle physics, the vacuum state is considered the basic state of matter. In applied physics and engineering, on the other hand, it is probably more helpful to view vacuum as a negative pressure, as this is the force that can be harnessed to do work. The pressure controlled by a vacuum pump can be a powerful force. In a vacuum system, it is the differential between the atmospheric pressure and the vacuum (negative) pressure that creates the ability to lift, hold, move, and perform many types of work. Atmospheric pressure – the pressure we’re all under Atmospheric pressure is the pressure of the weight of the air above us. A cross section of a column of air, measured from sea level to the top of the atmosphere, would exert a pressure of approximately 14.7 pounds per square inch (psi).
    [Show full text]
  • Arxiv:1810.10187V3 [Physics.Ins-Det] 10 Jan 2019 to Minimize Longitudinal Heat flow While Satisfying One’S Electrical Impedance and Shape (E.G
    Properties of selected structural and flat flexible cabling materials for low temperature applications M. Daala,∗, N. Zobrista, N. Kellarisd,e, B. Sadouletb, M. Robertsonc aDepartment of Physics, University of California, Santa Barbara CA 93106-9530 bDepartment of Physics, University of California, Berkeley CA 94720-7300 cDepartment of Physics, University of California, Davis CA 95616-8677 dDepartment of Mechanical Engineering, University of Colorado Boulder, 80309-0427 eMaterials Science and Engineering Program, University of Colorado, Boulder, 80309-0596 Abstract We present measurements of the low temperature thermal conductivity for materials useful in the construction of cryogenic supports for scientific instrumentation and in the fabrication of flat flexible cryogenic cabling. The materials we measure have relatively low thermal conductivity. We present a method for measuring the heat transfer coefficient of flat cabling and show, using an example, that the thermal conductivity of a flex cable is reasonably well predicted by composing the thermal conductivities of its constituent material layers. Room temperature physical and mechanical data is given for the materials studied, as well as an overview of relevant materials science and manufacturing details. Materials include Timet Ti 15-3 and Ti 21S, Materion alloy vit105 (LM105) in amorphous state, ATI Metals Nb-47Ti, Johnson Matthey nitinol (NiTi), Mersen graphite grade 2020, DuPont Pyralux coverlay and Vespel SCP-5050, and Fralock Cirlex polyimide sheets. All data is in the temperature range 0:05 to 2 K, and up to 5 K for SCP-5050. Keywords: Thermal conductivity, Heat transfer coefficient, Cryogenic, Structural materials, Support structures, Flat flexible cables, Superconducting cables, Low temperature, Titanium alloys, Bulk metallic glass, vit105, LM105, Cirlex, Vespel, Pyralux, NbTi, Ti 15-3-3-3, Ti 21S, Nitinol, NiTi, Transition Temperature 1.
    [Show full text]
  • DUPONT DATA BOOK SCIENCE-BASED SOLUTIONS Dupont Investor Relations Contents 1 Dupont Overview
    DUPONT DATA BOOK SCIENCE-BASED SOLUTIONS DuPont Investor Relations Contents 1 DuPont Overview 2 Corporate Financial Data Consolidated Income Statements Greg Friedman Tim Johnson Jennifer Driscoll Consolidated Balance Sheets Vice President Director Director Consolidated Statements of Cash Flows (302) 999-5504 (515) 535-2177 (302) 999-5510 6 DuPont Science & Technology 8 Business Segments Agriculture Electronics & Communications Industrial Biosciences Nutrition & Health Performance Materials Ann Giancristoforo Pat Esham Manager Specialist Safety & Protection (302) 999-5511 (302) 999-5513 20 Corporate Financial Data Segment Information The DuPont Data Book has been prepared to assist financial analysts, portfolio managers and others in Selected Additional Data understanding and evaluating the company. This book presents graphics, tabular and other statistical data about the consolidated company and its business segments. Inside Back Cover Forward-Looking Statements Board of Directors and This Data Book contains forward-looking statements which may be identified by their use of words like “plans,” “expects,” “will,” “believes,” “intends,” “estimates,” “anticipates” or other words of similar meaning. All DuPont Senior Leadership statements that address expectations or projections about the future, including statements about the company’s strategy for growth, product development, regulatory approval, market position, anticipated benefits of recent acquisitions, timing of anticipated benefits from restructuring actions, outcome of contingencies, such as litigation and environmental matters, expenditures and financial results, are forward looking statements. Forward-looking statements are not guarantees of future performance and are based on certain assumptions and expectations of future events which may not be realized. Forward-looking statements also involve risks and uncertainties, many of which are beyond the company’s control.
    [Show full text]
  • Outgassing of Technical Polymers PEEK, Kapton, Vespel & Mylar
    Ivo Wevers Outgassing of Technical Polymers PEEK, Kapton, Vespel & Mylar Vacuum, Surfaces & Coatings Group Technology Department Outline • Part 1: Introduction • Polymers in vacuum technology • Outgassing of water : metallic surface vs polymer • Part 2: Outgassing at Room Temperature • Outgassing measurements of PEEK, Kapton, Mylar and Vespel samples • Fitting with 2-step and 3-step models • Diffusion coefficient, moisture content and decay time constant • Part 3: Attenuation of Polymers Outgassing • Effects of bakeout and venting on pump-down curves • Effects of desication with silica gel • Conclusions & Future Vacuum, Surfaces & Coatings Group Ivo Wevers ARIES 2021 Technology Department 2 Part 1: Introduction • Polymers in vacuum technology • Outgassing of water : metallic surface vs polymer Vacuum, Surfaces & Coatings Group Ivo Wevers ARIES 2021 Technology Department 3 Polymers in vacuum technology Polymers are sometimes the only option as seal/insulator PEEK, Kapton and Vespel -> bakeout temperatures of 150-200C° Vacuum, Surfaces & Coatings Group Ivo Wevers ARIES 2021 Technology Department 4 Polymers in vacuum technology Polymers are sometimes the only option as seal/insulator PEEK, Kapton and Vespel -> bakeout temperatures of 150-200C° Guarantee a certain beam lifetime or certain operation conditions Outgassing limit (maximum pressure to be reached in 24 hours) is defined for each machine AND the residual gas analysis free of contaminants Acceptance test prior to installation: - Pumpdown will define the outgassing rate and variation
    [Show full text]
  • Radford's Cyclopedia of Construction; Carpentry, Building and Architecture
    1 Presented to the LIBRARY of the ^ UNIVERSITY OF TORONTO by MR. <ScMR3. J.C. MOORE Radford's Cyclopedia of Construction Carpentry, Building and Architecture A General Reference Work on MODERN BUILDING MATERIALS AND METHODS AND THEIR PRACTICAL AP' PLICATION TO ALL FORMS OF CONSTRUCTION IN WOOD, STONE. BRICK. STEEL, AND CONCRETE; INCLUDING ALSO SUCH ALLIED BRANCHES OF THE STRUCTURAL FIELD AS HEATING AND VENTILATING, PLUMBING, ELECTRIC WIRING, PAINTING, CONTRACTS, SPECI- FICATIONS, ESTIMATING, STRUCTURAL DRAFTING, ETC. Based on th". Practical Experience of a LARGE STAFF OF EXPERTS IN ACTUAL CONSTRUCTION WORK Illustrated TWELVE VOLUMES THE RADFORD ARCHITECTURAL COMPANY CHICAGO, ILL. Copyright, 1909 BY THE KADFOKD AKCHITECTUKAL COMPAN-S Radford's Cyclopedia of Construction Prepared under the Supervision of WILLIAM A. RADFORD Editor-in-Chief President of the Radford Architectural Company, Chicago, III. Editor-in-Chief of the "American Carpenter and Builder" and the "Cement World" ALFRED SIDNEY JOHNSON, A. M., Ph. D. Editor in Charge Author of "The Materials and Manufacture of Concrete," etc. Formerly Editor of "Cuncnt History." Associate Editor of Numerous Standard Works of Reference Partial List of Authors and Collaborators JOHN P. BROOKS, M. S. Associate Professor of Civil Engineering, and Acting Head of Department of Civil Engineering, University of Illinois FRANK O. DUFOUR, C. E. Assistant Professor of Structural Engineering, University of IlUn- nois Author of "Bridge Engineering," "Roof Trusses," etc. DAVID P. MORETON, B. S. Associate Professor of Electrical Engineering, Armour Institute of Technology ALFRED G. KING Consulting Engineer on Heating and Ventilating Author of "Practical Steam and Hot-Water Heating and Ventila- tion," "Steam and Hot-Water Heating Charts," "Practical Heating Illustrated," etc.
    [Show full text]
  • Dupont™ Kalrez® KVSP™ Valve Stem Packing Technical Guidelines and Design to Improve Process Control and Minimize Fugitive Emissions
    DuPont™ Kalrez® KVSP™ Valve Stem Packing Technical Guidelines and Design to Improve Process Control and Minimize Fugitive Emissions Technical Information—Rev. 4, March 2019 Introduction DuPont™ Kalrez® Valve Stem Packing (KVSP™) systems can help to significantly reduce fugitive emissions and improve process control through the innovative use of Kalrez® perfluoroelastomer parts combined with other proven packing materials. Graphite packing systems can meet fugitive emissions requirements but restrict valve movement, leading to inconsistent process control. Polytetrafluoroethylene (PTFE) has excellent process control response characteristics but cannot contain fugitive emissions when temperature cycling is involved in conjunction with operational cycling. Kalrez® packing systems overcome these deficiencies, as well as reducing leak rates to near-bellows performance. Kalrez® is chemically an elastomeric PTFE derived from tetrafluoroethylene (TFE), the same base monomer. It provides a unique combination of chemical resistance and inertness like PTFE, but with a higher temperature service limit and no tendency to cold flow. The chemical structure remains cross-linked and stable at high temperatures and does not move under load or deformation. Its resiliency and memory provide improved sealing for control valve stems. Using Kalrez® V-rings backed up with more rigid components of carbon fiber-reinforced PTFE (DuPont™ Vespel® CR-6100) has proven to be a major advancement in improving process control and reducing leakage to less than 1 ppm, or below the plant’s background level. Kalrez® perfluoroelastomer packing systems increase a valve’s ability to react quickly and smoothly to process changes (Figure 1). Kalrez® KVSP™ reduces process control variability to the control system’s capability, resulting in improvements to both yield and product quality on specification.
    [Show full text]
  • 18Th Annual Eastern Conference of the Timber Framers Guild
    Timber Framers Guild 18th Annual Eastern Conference November 14–17, 2002, Burlington, Vermont The Timber Framer’s Panel Company www.foardpanel.com P.O. Box 185, West Chesterfield, NH 03466 ● 603-256-8800 ● [email protected] Contents FRANK BAKER Healthy Businesses. 3 BRUCE BEEKEN Furniture from the Forest . 4 BEN BRUNGRABER AND GRIGG MULLEN Engineering Day to Day ENGINEERING TRACK . 6 BEN BRUNGRABER AND DICK SCHMIDT Codes: the Practical and the Possible ENGINEERING TRACK . 8 RUDY CHRISTIAN Understanding and Using Square Rule Layout WORKSHOP . 13 RICHARD CORMIER Chip Carving PRE-CONFERENCE WORKSHOP . 14 DAVID FISCHETTI AND ED LEVIN Historical Forms ENGINEERING TRACK . 15 ANDERS FROSTRUP Is Big Best or Beautiful? . 19 ANDERS FROSTRUP Stave Churches . 21 SIMON GNEHM The Swiss Carpenter Apprenticeship . 22 JOE HOWARD Radio Frequency Vacuum Drying of Large Timber: an Overview . 24 JOSH JACKSON Plumb Line and Bubble Scribing DEMONSTRATION . 26 LES JOZSA Wood Morphology Related to Log Quality. 28 MICHELLE KANTOR Construction Law and Contract Management: Know your Risks. 30 WITOLD KARWOWSKI Annihilated Heritage . 31 STEVE LAWRENCE, GORDON MACDONALD, AND JAIME WARD Penguins in Bondage DEMO 33 ED LEVIN AND DICK SCHMIDT Pity the Poor Rafter Pair ENGINEERING TRACK . 35 MATTHYS LEVY Why Buildings Don’t Fall Down FEATURED SPEAKER . 37 JAN LEWANDOSKI Vernacular Wooden Roof Trusses: Form and Repair . 38 GORDON MACDONALD Building a Ballista for the BBC . 39 CURTIS MILTON ET AL Math Wizards OPEN ASSISTANCE . 40 HARRELSON STANLEY Efficient Tool Sharpening for Professionals DEMONSTRATION . 42 THOMAS VISSER Historic Barns: Preserving a Threatened Heritage FEATURED SPEAKER . 44 Cover illustration of the Norwell Crane by Barbara Cahill.
    [Show full text]
  • Application of Polyimide Actuator Rod Seals
    (NASA-CR- 120878) APPLICATION OF POLYIiIDE N72-245306 ACTUATOR ROD SEALS AoH. Hatermann, et al (Boeing Co,, Seattle, Wash,) 30 Jan. 1972 177 p CSCL 11A Unclas G3/15 28867 I CR-I 20878 D6-54351 A A~ APPLICATION OF POLYIMIDE ACTUATOR ROD SEALS by A. W. Waterman, B. F. Gay, E. D. Robinson, S. K. Srinath, W. G. Nelson THE BOEING COMPANY prepared for NATIONAL AERONAUTICS AND SPACE ADMINISTRATION NASA Lewis Research Center Contract NAS3-14317 ! William F. Hady, Project Manager 1. Report No. 2. Government Accession No. 3. Recipient's Catalog No. CR- 120878 4. Title and Subtitle 5. Report Date APPLICATION OF POLYIMIDE ACTUATOR ROD SEALS January 30, 1972 6. Performing Organization Code 7. Author(s) A. W. Waterman, B. F. Gay, E. D. Robinson, 8. Performing Organization Report No. S. K. Srinath, and W. G. Nelson D6-54351 9. Performing Organization Name and Address 10. Work Unit No. YON 1347 The Boeing Company, Commercial Airplane Group 11. Contractor Grant No. P.O. Box 3707, Seattle, Washington 98124 NAS3-14317 13. Type of Report and Period Covered 12. Sponsoring Agency Name and Address CONTRACTOR REPORT National Aeronautics and Space Administration 7/1/70-1/30/72 Washington, D.C. 20546 14. Sponsoring Agency Code 15. Supplementary Notes Project Manager: W. F. Hady, Fluid System Component Division, NASA Lewis Research Center, Cleveland, Ohio 16. Abstract Development of polyimide two-stage hydraulic actuator rod seals for application in high-performance aircraft was accomplished. The significant portion of the effort was concentrated on optimization of the chevron and K-section second-stage seal geometries to satisfy the requirements for operation at 4500K (3500F) with dynamic pressure loads varying between 1.379 x 106 N/m2 (200 psig) steady-state and 1.043 x 107 N/m2 (1500 psig) impulse cycling.
    [Show full text]
  • Introduction to the Principles of Vacuum Physics
    1 INTRODUCTION TO THE PRINCIPLES OF VACUUM PHYSICS Niels Marquardt Institute for Accelerator Physics and Synchrotron Radiation, University of Dortmund, 44221 Dortmund, Germany Abstract Vacuum physics is the necessary condition for scientific research and modern high technology. In this introduction to the physics and technology of vacuum the basic concepts of a gas composed of atoms and molecules are presented. These gas particles are contained in a partially empty volume forming the vacuum. The fundamentals of vacuum, molecular density, pressure, velocity distribution, mean free path, particle velocity, conductivity, temperature and gas flow are discussed. 1. INTRODUCTION — DEFINITION, HISTORY AND APPLICATIONS OF VACUUM The word "vacuum" comes from the Latin "vacua", which means "empty". However, there does not exist a totally empty space in nature, there is no "ideal vacuum". Vacuum is only a partially empty space, where some of the air and other gases have been removed from a gas containing volume ("gas" comes from the Greek word "chaos" = infinite, empty space). In other words, vacuum means any volume containing less gas particles, atoms and molecules (a lower particle density and gas pressure), than there are in the surrounding outside atmosphere. Accordingly, vacuum is the gaseous environment at pressures below atmosphere. Since the times of the famous Greek philosophers, Demokritos (460-370 B.C.) and his teacher Leukippos (5th century B.C.), one is discussing the concept of vacuum and is speculating whether there might exist an absolutely empty space, in contrast to the matter of countless numbers of indivisible atoms forming the universe. It was Aristotle (384-322 B.C.), who claimed that nature is afraid of total emptiness and that there is an insurmountable "horror vacui".
    [Show full text]
  • Abana Controlled Hand Forging Study Guide As Paginated by the Guild of Metalsmiths - Abana Chapter - Jan 2020 Index
    ABANA CONTROLLED HAND FORGING STUDY GUIDE AS PAGINATED BY THE GUILD OF METALSMITHS - ABANA CHAPTER - JAN 2020 INDEX Lesson Number Number Description of Pages Credits (click on box) L 1.01 Drawing Out: Draw a sharp point on a 1/2" square bar 3 Peter Ross and Doug Wilson L 2.01 Hot Punching: Create holes or recesses in bars or plate by driving 2 By Doug Wilson Illustrations by Tom Latané punches into or through hot material. L 3.01 Drawing Out a Round Taper 3 By Jay Close Illustrations by Tom Latané L 4.01 Bending Bar Stock 5 By Jay Close Illustrations by Tom Latané L 5.01 Twisting a Square Bar 4 By Bob Fredell Illustrations by Tom Latané L 6.01 Drawing , Punching, and Bending 4 By Peter Ross Illustrations by Tom Latané L 7.01 Upsetting a Square Bar 3 By Peter Ross Illustrations by Tom Latané L 8.01 Slitting and Drifting Two Mortises or Slots in a Square Sectioned Bar 5 By Jay Close llustrations by Doug Wilson, photos by Jay Close L 9.01 Mortise and Tenon Joinery 3 Text and Illustrations by Doug Wilson L 10.01 Forge Welding 6 By Dan Nauman Illustrations by Tom Latané Photos by Dan Nauman L 11.01 Drawing Down - Part One 6 by Jay Close Illustrations by Tom Latané, photos by Jay Close and Jane Gulden L 11.07 Drawing Down - Part Two 6 by Jay Close Illustrations by Tom Latané, photos by Jay Close and Jane Gulden L 12.01 Forging a Shoulder 4 by Bob Fredell Illustrations by Tom Latané L 13.01 Cutting a Bar 2 by Dan Nauman Illustrations by Doug Wilson L 14.01 Forging a 90-degree Corner 3 Text and Photos by Dan Nauman L 15.01 Forge an Eye on the
    [Show full text]
  • BEGINNING WOODWORK at HOME and in SCHOOL —«V— Cumroh Uuloon Van Dcomm Class / / L^J
    ^ T T BEGINNING WOODWORK AT HOME AND IN SCHOOL —«v— cumroH uuLooN van dcomm Class / / L^J, Copyright N''- COPyKIGIlT DEPOSIT. m o BEGINNING WOODWORK At H o !•; and In S c h o i. Bv Clinton Sheldon Van Deusen, M. E. Initnicior in Mjnual Arts, Bradley Holytrchnic Inilitutc. Illuitiatcd iv Edwin Victor Lawrence, Inilruclor in Drawing, I'nivcrlit)- of lllinoii. The Manual Arts Prhss Peoria, Illinois <b ^ \ UBRARYofMMRESS A' Two eoBies Received FEB 14 1907 ^ C»pyrtEttt EntFV AaSS /( XX/..N*, COf-Y B. / COPVRJGHT The Manual Arts Press 1907 <]-%^'^0 FOREWORD This book is intended as a definite statement of steps that may be followed by a beginner in learning the fundamental principles of woodworking. Instead of giving a general discussion of wood- working processes, the book describes and illustrates principles by means of specific examples. The experience gained in doing these problems should enable one to master a large number of others of which these stand as types. It is believed that this method of treatment of the subject of woodworking will prove helpful in both school and home work. Clinton S. Van Deusen. CONTENTS PAGE Chapter I —Introduction 7 Dealing with the equipment, the care of the shop, the tools and materials, and a discussion of the principles of working drawings. Chapter II —Laying Out and Sawing 15 Detailed statement of the steps to bo followed in making a game board, with suggestions for making similar pieces. Chapter III —Planing 25 Steps to be followed in making a swing board, witli special thought as to the development of freedom in hamlling the plane.
    [Show full text]
  • Around the Laboratories
    Around the Laboratories such studies will help our under­ BROOKHAVEN standing of subnuclear particles. CERN Said Lee, "The progress of physics New US - Japanese depends on young physicists Antiproton encore opening up new frontiers. The Physics Centre RIKEN - Brookhaven Research Center will be dedicated to the t the end of 1996, the beam nurturing of a new generation of Acirculating in CERN's LEAR low recent decision by the Japanese scientists who can meet the chal­ energy antiproton ring was A Parliament paves the way for the lenge that will be created by RHIC." ceremonially dumped, marking the Japanese Institute of Physical and RIKEN, a multidisciplinary lab like end of an era which began in 1980 Chemical Research (RIKEN) to found Brookhaven, is located north of when the first antiprotons circulated the RIKEN Research Center at Tokyo and is supported by the in CERN's specially-built Antiproton Brookhaven with $2 million in funding Japanese Science & Technology Accumulator. in 1997, an amount that is expected Agency. With the accomplishments of these to grow in future years. The new Center's research will years now part of 20th-century T.D. Lee, who won the 1957 Nobel relate entirely to RHIC, and does not science history, for the future CERN Physics Prize for work done while involve other Brookhaven facilities. is building a new antiproton source - visiting Brookhaven in 1956 and is the antiproton decelerator, AD - to now a professor of physics at cater for a new range of physics Columbia, has been named the experiments. Center's first director. The invention of stochastic cooling The Center will host close to 30 by Simon van der Meer at CERN scientists each year, including made it possible to mass-produce postdoctoral and five-year fellows antiprotons.
    [Show full text]