Contents ix
5.5 Particle Classification ............................................... 109
5.5.1 Classification According to Stability ................... 110
5.5.2 Classification According to the Spin .................... 110
5.5.3 Classification According to the Baryon
and Lepton Numbers .................................... 111
6 Invariance and Conservation Principles ................................. 113
6.1 Introduction ......................................................... 113
6.2 Invariance Principle Reminder ..................................... 114
6.2.1 Invariance in Classical Mechanics ...................... 114
6.2.2 Invariance in Quantum Mechanics ..................... 115
6.2.3 Continuous Transformations: Translations
and Rotations ............................................ 117
6.3 Spin-Statistics Connection ......................................... 118
6.4 Parity ................................................................ 119
6.5 Spin-Parity of the Meson ........................................ 122
6.5.1 Spin of the Meson ..................................... 122
6.5.2 Parity of the Meson ................................... 123
6.5.3 Particle–Antiparticle Parity.............................. 125
6.6 Charge Conjugation................................................. 126
6.6.1 Charge Conjugation in Electromagnetic
Processes ................................................ 127
6.6.2 Violation of C in the Weak Interaction.................. 128
6.7 Time Reversal ....................................................... 129
6.8 CP and CPT ......................................................... 131
6.9 Electric Charge and Gauge Invariance ............................. 133
7 Hadron Interactions at Low Energies and the Static
Quark Model ............................................................... 135
7.1 Hadrons and Quarks ................................................ 135
7.1.1 The Yukawa Model ...................................... 136
7.2 Proton-Neutron Symmetry and the Isotopic Spin ................. 137
7.3 The Strong Interaction Cross-Section .............................. 139
7.3.1 Mean Free Path .......................................... 140
7.4 Low Energy Hadron-Hadron Collisions ........................... 142
7.4.1 Antibaryons .............................................. 143
7.4.2 Hadron Resonances ...................................... 144
7.5 Breit–Wigner Equation for Resonances ........................... 148
7.5.1 The
CC
.1232/ Resonance ............................. 150
7.5.2 Resonance Formation and Production .................. 151
7.5.3 Angular Distribution of Resonance Decay Products ... 152
7.6 Production and Decay of Strange Particles ........................ 154
7.7 Classification of Hadrons Made of u;d;s Quarks ................ 156
7.8 The J
P
=3/2
C
Baryonic Decuplet.................................. 158
7.8.1 First Indications for the Color Quantum Number ...... 160
7.9 The J
P
=1/2
C
Baryonic Octet ...................................... 162
7.10 Pseudoscalar Mesons ............................................... 163