Quarks Leptons And The Big Bang

Quarks, Leptons and the Big Bang
Second Edition

Quarks, Leptons and the Big Bang
Second Edition

Jonathan Allday
The King’s School, Canterbury

Institute of Physics Publishing Bristol and Philadelphia

c IOP Publishing Ltd 2002 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic,mechanical, photocopying, recording or otherwise, without the prior permission of the publisher. Multiple copying is permitted in accordance with the terms of licences issued by the Copyright Licensing Agency under the terms of its agreement with the Committee of ViceChancellors and Principals. British Library Cataloguing-in-Publication Data A catalogue record for this book is available from theBritish Library. ISBN 0 7503 0806 0 Library of Congress Cataloging-in-Publication Data are available First edition printed 1998 First edition reprinted with minor corrections 1999

Commissioning Editor: James Revill Production Editor: Simon Laurenson Production Control: Sarah Plenty Cover Design: Fr´ d´ rique Swist e e Marketing Executive: Laura Serratrice Published by Institute of PhysicsPublishing, wholly owned by The Institute of Physics, London Institute of Physics Publishing, Dirac House, Temple Back, Bristol BS1 6BE, UK US Office: Institute of Physics Publishing, The Public Ledger Building, Suite 1035, 150 South Independence Mall West, Philadelphia, PA 19106, USA
A Typeset in LTEX 2ε by Text 2 Text, Torquay, Devon Printed in the UK by MPG Books Ltd, Bodmin, Cornwall

ContentsPreface to the second edition Preface to the first edition Prelude: Setting the scene 1 The standard model 1.1 The fundamental particles of matter 1.2 The four fundamental forces 1.3 The big bang 1.4 Summary of chapter 1 Aspects of the theory of relativity 2.1 Momentum 2.2 Kinetic energy 2.3 Energy 2.4 Energy and mass 2.5 Reactions and decays 2.6 Summary of chapter 2 Quantum theory 3.1 The doubleslot experiment for electrons 3.2 What does it all mean? 3.3 Feynman’s picture 3.4 A second experiment 3.5 How to calculate with amplitudes 3.6 Following amplitudes along paths 3.7 Amplitudes, states and uncertainties 3.8 Summary of chapter 3

ix xiii 1 5 5 10 14 18 21 21 28 31 32 37 40 42 44 49 50 53 56 59 72 82

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Contents The leptons 4.1 A spotter’s guide to the leptons 4.2The physical properties of the leptons 4.3 Neutrino reactions with matter 4.4 Some more reactions involving neutrinos 4.5 ‘Who ordered that?’ 4.6 Solar neutrinos again 4.7 Summary of chapter 4 Antimatter 5.1 Internal properties 5.2 Positrons and mystery neutrinos 5.3 Antiquarks 5.4 The general nature of antimatter 5.5 Annihilation reactions 5.6 Summary of chapter 5 Hadrons 6.1 The properties ofthe quarks 6.2 A review of the strong force 6.3 Baryons and mesons 6.4 Baryon families 6.5 Meson families 6.6 Internal properties of particles 6.7 Summary of chapter 6 Hadron reactions 7.1 Basic ideas 7.2 Basic processes 7.3 Using conservation laws 7.4 The physics of hadron reactions 7.5 Summary of chapter 7 Particle decays 8.1 The emission of light by atoms 8.2 Baryon decay 8.3 Meson decays 8.4Strangeness 8.5 Lepton decays 8.6 Summary of chapter 8 The evidence for quarks 9.1 The theoretical idea 85 85 87 89 93 95 98 99 101 101 107 110 112 114 116 118 118 122 123 124 129 131 132 134 134 135 140 142 147 148 148 149 162 164 165 166 167 167

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Contents 9.2 9.3 9.4 9.5 Deep inelastic scattering Jets The November revolution Summary of chapter 9

vii 167 173 178 179181 181 182 188 190 197 201 203 210 210 217 222 234 236 237 238 241 244 244 251 265 267 267 269 272 276 279 281 284 284 286 298 315

10 Experimental techniques 10.1 Basic ideas 10.2 Accelerators 10.3 Targets 10.4 Detectors 10.5 A case study—DELPHI 10.6 Summary of chapter 10 Interlude 1: CERN 11 Exchange forces 11.1 The modern approach to forces 11.2 Extending the idea 11.3 Quantum field theories...