Particle Accelerator Physics I: Basic Principles and Linear Beam Dynamics

464 Pages·1999·0.46 MB·English

by  Professor Dr. Helmut Wiedemann (auth.)

Particle Accelerator Physics I
Springer-Verlag Berlin Heidelberg GmbH
Helmut Wiedemann
Particle
Accelerator Physics I
Basic Principles
and Linear Beam Dynamics
Second Edition
With 160 Figures
Springer
Professor Dr. Helmut Wiedemann
Applied Physics Department
and Synchrotron Radiation Laboratory
Stanford University, Stanford, CA 94309.0210, USA
e-mail: [email protected]
ISBN 978-3-662-03829-1 ISBN 978-3-662-03827-7 (eBook)
DOI 10.1007/978-3-662-03827-7
Library of Congress Cataloging-in-Publication Data.
Wiedemann, Helmut, 1938-Particle accelerator physics I : basic principles and linear beam dynamics I
Helmut Wiedemann. -2nd ed. p.cm. Includes bibliographical references and index. ISBN 978-3-662-03829-1
1. Beam dynamics. 2. Linear accelerators. I. Title. QC793.3.B4 W54 1998 539.7'3-
ddc2l 98-46048 CIP
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© Springer-Verlag Berlin Heidelberg 1993, 1999
Originally published by Springer-Verlag Berlin Heidelberg New York in 1999
Softcover reprint of the hardcover 2nd edition 1999
The use of general descriptive names, registered names, trademarks, etc. in this publication does not
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To my sons
Frank and Martin
Preface
In this second edition of Particle Accelerator Physics, Vol. 1, is mainly
a reprint of the first edition without significant changes in content. The
bibliography has been updated to include more recent progress in the field
of particle accelerators.
With the help of many observant readers a number of misprints and
errors could be eliminated. The author would like to express his sincere
appreciation to all those who have pointed out such shortcomings and wel
comes such information and any other relevant information in the future.
The author would also like to express his special thanks to the editor
Dr. Helmut Lotsch and his staff for editorial as well as technical advice and
support which contributed greatly to the broad acceptance of this text and
made a second edition of both volumes necessary.
Palo Alto, California Helmut Wiedemann
November 1998
VII
Preface to the First Edition
The purpose of this textbook is to provide a comprehensive introduction
into the physics of particle accelerators and particle beam dynamics. Parti
cle accelerators have become important research tools in high energy physics
as well as sources of incoherent and coherent radiation from the far infra
red to hard x-rays for basic and applied research. During years of teaching
accelerator physics it became clear that the single most annoying obstacle
to get introduced into the field is the absence of a suitable textbook. Indeed
most information about modern accelerator physics is contained in numer
ous internal notes from scientists working mostly in high energy physics
laboratories all over the world.
This text intends to provide a broad introduction and reference book
into the field of accelerators for graduate students, engineers and scientists
summarizing many ideas and findings expressed in such internal notes and
elsewhere. In doing so theories are formulated in a general way to become
applicable for any kind of charged particles. Writing such a text, however,
poses the problem of correct referencing of original ideas. I have tried to find
the earliest references among more or less accessible notes and publications
and have listed those although the reader may have difficulty to obtain the
original paper. In spite of great effort to be historically correct I apologize
for possible omissions and misquotes. This situation made it necessary to
rederive again some of such ideas rather than quote the results and refer the
interested reader to the original publication. I hope this approach will not
offend the original researchers, but rather provide a broader distribution of
their original ideas, which have become important to the field of accelerator
physics.
This text is split into two volumes. The first volume is designed to be self
contained and is aimed at newcomers into the field of accelerator physics,
but also to those who work in related fields and desire some background on
basic principles of accelerator physics. The first volume therefore gives an
introductory survey of fundamental principles of particle acceleration fol
lowed by the theory of linear beam dynamics in the transverse as well as
longitudinal phase space including a detailed discussion of basic magnetic
focusing units. Concepts of single and multi particle beam dynamics are in
troduced. Synchrotron radiation, its properties and effect on beam dynamics
and electron beam parameters is described in considerable detail followed
IX
by a discussion of beam instabilities on an introductory level, beam lifetime
and basic lattice design concepts.
The second volume is aimed specifically to those students, engineers and
scientists who desire to immerse themselves deeper into the physics of par
ticle accelerators. It introduces the reader to higher order beam dynamics,
Hamiltonian particle dynamics, general perturbation theory, nonlinear beam
optics, chromatic and geometric aberrations and resonance theory. The in
teraction of particle beams wi th rf fields of the accelerating system and beam
loading effects are described in some detail relevant to accelerator physics.
Following a detailed derivation of the theory of synchrotron radiation, par
ticle beam phenomena are discussed while utilizing the Vlasov and Fokker
Planck equations leading to the discussion of beam parameters and their
manipulation and collective beam instabilities. Finally design concepts and
new developments of particle accelerators as synchrotron radiation sources
or research tools in high energy physics are discussed in some detail.
This text grew out of a number of lecture notes for accelerator physics
courses at Stanford University, the Synchrotron Radiation Research Labo
ratory in Taiwan, the University of Sao Paulo in Brazil, the International
Center for Theoretical Physics in Trieste and the US Particle Accelerator
School as well as from interaction with students attending those classes and
my own graduate students.
During almost thirty years in this field I had the opportunity to work
with numerous individuals and accelerators in laboratories around the
world. Having learned greatly from these interactions I like to take this
opportunity to thank all those who interacted with me and have had the
patience to explain their ideas, share their results or collaborate with me.
The design and construction of new particle accelerators provides a specifi
cally interesting period to develop and test theoretically new ideas, to work
with engineers and designers, to see theoretical concepts become hardware
and to participate in the excitement of commissioning and optimization. I
have had a number of opportunities for such participation at the Deutsches
Elektronen Synchrotron DESY in Hamburg, Germany and at the Stanford
University at Stanford, California and am grateful to all colleagues who
hosted and collaborated with me. I wished I could mention them individu
ally and apologize for not doing so.
A special thanks goes to the operators of the electron storage rings
SPEAR and PEP at the Stanford Linear Accelerator Center, specifically
to T. Taylor, W. Graham, E. Guerra and M. Maddox, for their dedicated
and able efforts to provide me during numerous shifts over many years with
a working storage ring ready for machine physics experimentation.
I thank Mrs. Joanne Kwong, who typed the initial draft of this texts and
introduced me into the intricacies of TEX typesetting. The partial support
by the Department of Energy through the Stanford Synchrotron Radiation
Laboratory in preparing this text is gratefully acknowledged. Special thanks
x
to Dr. C. Maldonado for painstakingly reading the manuscript. Last but not
least I would like to thank my family for their patience in dealing with an
"absent" husband and father.
Palo Alto, California Helmut Wiedemann
April 1993
XI
Contents
1. Introduction .......................................... . 1
1.1 Short Historical Overview .......................... . 1
1.2 Particle Accelerator Systems ....................... . 5
1.2.1 Basic Components of Accelerator Facilities .... . 5
1.2.2 Applications of Particle Accelerators ......... . 8
1.3 Basic Definitions and Formulas ..................... . 9
1.3.1 Units and Dimensions ...................... . 9
1.3.2 Basic Relativistic Formalism ................. . 12
1.3.3 Particle Collisions at High Energies .......... . 15
1.4 Basic Principles of Particle-Beam Dynamics .......... . 17
1.4.1 Stability of a Charged-Particle Beam ......... . 20
Problems 21
2. Linear Accelerators .................................... . 25
2.1 Principles of Linear Accelerators .................... . 25
2.1.1 Charged Particles in Electric Fields .......... . 25
2.1.2 Electrostatic Accelerators ................... . 27
2.1.3 Induction Linear Accelerator ................ . 30
2.2 Acceleration by rf Fields ........................... . 31
2.2.1 Basic Principle of Linear Accelerators ........ . 31
2.2.2 Waveguides for High Frequency EM Waves .... . 33
2.3 Preinjector Beam Preparation ...................... . 47
2.3.1 Prebuncher ................................ . 47
2.3.2 Beam Chopper ............................ . 49
Problems 50
3. Circular Accelerators .................................. . 53
3.1 Betatron ......................................... . 54
3.2 Weak Focusing ................................... . 58
3.3 Adiabatic Damping ............................... . 60
3.4 Acceleration by rf Fields ........................... . 62
3.4.1 Microtron ................................. . 63
3.4.2 Cyclotron ................................. . 65
3.4.3 Synchro Cyclotron ......................... . 67
3.4.4 Isochron Cyclotron ......................... . 68
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