An Introduction to Gauge Theories and Modern Particle Physics 2 Volume Hardback Set (Cambridge Monographs on Particle Physics, Nuclear Physics and Cosmology) (Vol.1)

543 Pages·1996·4.46 MB·English

by  Elliot Leader

An introduction
theories
to gauge
and modern
particle physics
Volume 1
Electroweak interactions,
the "new particles" and the parson model
E LLI OT LEADER
ENRICO PREDAZZI
CAMBRIDGE MONOGRAPHS
ON PARTICLE PHYSICS,
NUCLEAR PHYSICS AND COSMOLOGY
3
The revolution in elementary particle physics sparked by the unearthing of the
bizarre J/'Y particle in 1974 and followed by the discovery of the equally myste-
rious -r and T particles, led to a beautiful interweaving of theory and experiment
culminating in the Salam-Weinberg theory of electroweak interactions and the
quantum chromodynamic (QCD) theory of strong interactions. The extraordi-
nary prediction of the W and Z° bosons was fulfilled in 1983, and it is now
possible to produce Z° in millions. The emphasis today is on refined testing of
the detailed quantitative predictions of the theories, and, to match this, more
sophisticated calculations are demanded. This book presents, in two volumes,
a comprehensive and unified treatment of modern theoretical and experimental
particle physics at a level accessible to beginning research students. The empha-
sis throughout is on presenting underlying physical principles in a simple and
intuitive way, and the more sophisticated methods demanded by present-day
research interests are introduced in a very gradual and gentle fashion.
Volume 1 covers electroweak interactions, the discovery and properties of the
`new' particles, the discovery of partons and the construction and predictions
of the simple parton model. Volume 2 deals at some length with CP violation,
but is mainly devoted to QCD and its application to `hard' processes. A brief
coverage of soft hadronic physics and of non-perturbative QCD is included.
This work will provide a comprehensive reference and textbook for all graduate
students and researchers interested in modern particle physics.

CAMBRIDGE MONOGRAPHS ON
PARTICLE PHYSICS,
NUCLEAR PHYSICS AND COSMOLOGY
3
General Editors: T. Ericson, P. V. Landshoff
AN INTRODUCTION TO GAUGE THEORIES AND
MODERN PARTICLE PHYSICS, VOLUME 1
CAMBRIDGE MONOGRAPHS ON
PARTICLE PHYSICS,
NUCLEAR PHYSICS AND COSMOLOGY
1. K. Winter (ed.): Neutrino Physics
2. J. F. Donoghue, E. Golowich and B. R. Holstein: Dynamics of the Standard Model
3. E. Leader and E. Predazzi: An Introduction to Gauge Theories and Modern Particle
Physics, Volume 1: Electroweak interactions, the `new particles' and the parton model
4. E. Leader and E. Predazzi: An Introduction to Gauge Theories and Modern Particle
Physics, Volume 2: CP violation, QCD and hard processes
AN INTRODUCTION
TO GAUGE THEORIES
AND MODERN
PARTICLE PHYSICS,
VOLUME 1
Electroweak interactions, the `new particles' and the parton model
ELLIOT LEADER
Birkbeck College, University of London
ENRICO PREDAZZI
University of Torino
AMBRIDGE
UNIVERSITY PRESS
Published by the Press Syndicate of the University of Cambridge
The Pitt Building, Trumpington Street, Cambridge CB2 1RP
40 West 20th Street, New York, NY 10011-4211, USA
10 Stamford Road, Oakleigh, Melbourne 3166, Australia
© Cambridge University Press 1996
First published 1996
A catalogue record for this book is available from the British Library
Library of Congress cataloguing in publication data
Leader, Elliot, 1935-
An introduction to gauge theories and modern particle physics /
Elliot Leader, Enrico Predazzi.
p. cm. - (Cambridge monographs on particle physics,
nuclear physics, and cosmology; 3-4)
Includes bibliographical references and index.
Contents: v. 1. Electroweak interactions, the "new particles"
and the parton model - v. 2. CP-violation, QCD and hard processes.
ISBN 0 521 46468 4 (v.1) - ISBN 0 521 46840 X (pbk. v. 1.) -
ISBN 0 521 49617 9 (v. 2). - ISBN 0 521 499518 (pbk. v.2)
1. Gauge fields (Physics) 2. Particles (Nuclear physics)
1. Predazzi, Enrico. II. Title. III. Series.
QC793.3.G38L43 1996
539.7'54-dc2O 95-25233 CIP
Vol. 1 ISBN 0 521 46468 4 hardback
ISBN 0 521 46840 X paperback
Vol. 2 ISBN 0 521 49617 9 hardback
ISBN 0 521 49951 8 paperback
Set of two vols.
ISBN 0 521 57780 2 hardback
ISBN 0 521 57742 X paperback
Transferred to digital printing 2004
TAG
Dedication
To our children, Darian, Francesca, Imre, Irene and Valentina.
Perche si scrive?
... Per insegnare qualcosa a qualcuno. Farlo, e farlo bene, pub
essere prezioso per ii lettore, ma ... l'intento didattico corrode la tela
narrativa dal di sotto, la degrada e la inquina: it lettore the cerca it
racconto deve trovare it racconto, e non una lezione the non desidera.
Ma appunto, le eccezioni ci sono, e chi ha sangue di poeta sa trovare
ed esprimere poesia anche parlando di stelle, di atomi, dell'alleva-
mento del bestiame e dell'apicultura...
Why does one write?
... To teach something to someone. To do this and do it well
can be valuable for the reader but ... the didactic intention corrodes
the narrative canvas from underneath, degrades it and contaminates
it: the reader who looks for a story must find a story and not a lesson
he does not want. But, of course, exceptions there are, and whoever
has the blood of a poet will find and express poetry also when talking
of stars, of atoms, of cattle breeding and of the raising of bees...
Primo Levi
Contents: Volume 1
Electroweak interactions, the
`new particles' and the
parton model
Preface xxi
Acknowledgements xxiv
Notational conventions xxv
Note added in proof: the discovery of the top quark (?) xxxi
Note added in proof: the demise of the SSC xxxiii
1 Field theory and pre-gauge theory of weak interactions 1
1.1 A brief introduction to field theory 1
1.2 Pre-gauge theory of weak interactions 6
1.3 The spin and isospin structure 15
1.3.1 The spin or helicity structure 16
1.3.2 Relation between particle and antiparticle matrix elements 17
1.3.3 The isospin structure 18
1.4 Tests of the V-A structure and `lepton universality' 20
2 The need for a gauge theory 23
2.1 The intermediate vector boson 23
2.2 Towards a renormalizable theory 27
2.3 Gauge symmetry 29
2.3.1 Global gauge invariance-the Abelian case 30
2.3.2 Local gauge invariance-the Abelian case 31
2.3.3 Global gauge invariance-the non-Abelian case 33
2.3.4 Non-Abelian local gauge invariance-Yang-Mills theories 35
2.4 Freedom to choose the gauge 38
2.5 Summary 39
3 Spontaneous symmetry breaking: the Goldstone theorem
and the Higgs phenomenon
40
3.1 Spontaneously broken symmetries in field theory: Goldstone's
theorem
41
ix