# An Introductory Course of Particle Physics

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## Book Description

For graduate students unfamiliar with particle physics, **An Introductory Course of Particle Physics **teaches the basic techniques and fundamental theories related to the subject. It gives students the competence to work out various properties of fundamental particles, such as scattering cross-section and lifetime. The book also gives a lucid summary of the main ideas involved.

In giving students a taste of fundamental interactions among elementary particles, the author does not assume any prior knowledge of quantum field theory. He presents a brief introduction that supplies students with the necessary tools without seriously getting into the nitty-gritty of quantum field theory, and then explores advanced topics in detail. The book then discusses group theory, and in this case the author assumes that students are familiar with the basic definitions and properties of a group, and even SU(2) and its representations. With this foundation established, he goes on to discuss representations of continuous groups bigger than SU(2) in detail.

The material is presented at a level that M.Sc. and Ph.D. students can understand, with exercises throughout the text at points at which performing the exercises would be most beneficial. Anyone teaching a one-semester course will probably have to choose from the topics covered, because this text also contains advanced material that might not be covered within a semester due to lack of time. Thus it provides the teaching tool with the flexibility to customize the course to suit your needs.

## Table of Contents

**Scope of Particle Physics **What are elementary particles?

Inventory of Elementary Fermions

Which Properties?

Fundamental Interactions

High Energy Physics

Relativity and Quantum Theory

Natural Units

Plan of the book

**Relativistic Kinematics**

Lorentz Transformation Equations

Vectors and Tensors on Spacetime

Velocity, Momentum and Energy

Covariance

Invariances and Conservation Laws

Kinematics of Decays

Kinematics of Scattering Processes

**Symmetries and Groups**

The Role of Symmetries

Group Theory

Examples and Classification

Generators

Representations

Lorentz Group

Poincaré Group

**A brisk Tour of Quantum Field Theory**

Motivating quantum fields

Plane wave solutions

Lagrangian

Making Lorentz Invariants with Fields

Lagrangians for Free Fields

Noether Currents and Charges

Quantum Fields as Operators

States

Interactions

From Lagrangian to Feynman rules

Calculation of Decay Rates

Calculation of Cross-Sections

Differential Decay Rates and Cross-Sections

Feynman Diagrams Which Do Not Represent Physical Amplitudes

**Quantum Electrodynamics**

Gauge Invariance

Interaction Vertex

Elastic Scattering at Second Order

Inelastic Scattering at Second Order

Scalar QED

Multi-Photon States

Higher Order Effects

**Parity and Charge Conjugation**

Discrete Symmetries in Classical Electrodynamics

Parity Transformation of Fields

Charge Conjugation

Parity Properties of Particle States

Charge Conjugation Properties of Particle States

Multi-Photon States

Positronium

Parity Assignment of Different Particles

Signature of Parity Violation

Consequences of Charge Conjugation Symmetry

CP Symmetry

**Time-Reversal and CPT Symmetries**

Anti-Unitary Operators

Time Reversal Transformation on Fields

CPT Transformation on Fields

CPT Theorem

Consequences of CPT Symmetry

Time Reversal Transformation on States

Signature of Time Reversal Violation

**Isospin**

Nuclear Energy Levels

Isospin Symmetry

Pions

Isospin Relations

G-parity

Generalized Pauli Principle

Isospin and Quarks

Pion-Nucleon Interaction

Isospin breaking

Baryon Number**Discovering Particles **Discoveries of Electron, Proton and Neutron

New Particles in Cosmic Rays

Accelerators

Detectors

Hadronic Zoo

Detecting Short-Lived Particles

Discovering Leptons

Overview of Particle Physics Experiments

**SU(3) quark model**

Strange quark

Hypercharge

SU(3)

Mesons from three flavors of quarks

Baryons from three flavors of quarks

U-spin and V -spin

SU(3) breaking and mass relations

Electromagnetic properties in SU(3)

Decays of hadrons

Summary of conservation laws

Color

**Non-Abelian Gauge Theories**

Local SU(N) invariance

Gauge fields

Self-interaction of gauge bosons

Fadeev–Popov ghosts

Interaction of gauge bosons with other particles

**Quantum Chromodynamics**

SU(3) of Color

Running Parameters

QCD Lagrangian

Perturbative QCD

The 1/N expansion

Lattice Gauge Theory

Confinement

Asymptotic Properties of Color Gauge Fields

**Structure of hadrons**

Electron-Proton Elastic Scattering

Deep Inelastic Scattering

Structure Functions and Charge Distribution

Scaling

Partons

Parton Distribution Functions

Parton Distribution and Cross-Section

Fragmentation

Scale Dependence of Parton Distribution

Quark Masses

Glueballs

**Fermi Theory of Weak Interactions**

Four-Fermion Interaction

Helicity and Chirality

Fierz Transformations

Elastic Neutrino-Electron Scattering

Inelastic Neutrino-Electron Scattering

Muon and Tau Decay

Parity Violation

Problems with Fermi Theory

Intermediate Vector Bosons

**Spontaneous Symmetry Breaking**

Examples of Spontaneous Symmetry Breaking

Goldstone Theorem

Interaction of Goldstone Bosons

Higgs Mechanism

**Standard Electroweak Model with Leptons**

Chiral Fermions and Internal Symmetries

Leptons and the Gauge Group

Symmetry Breaking

Gauge Interaction of Fermions

Yukawa Sector

Connection with Fermi Theory

Forward-Backward Asymmetry

**Electroweak Interaction of Hadrons**

Quarks in Standard Model

Gauge Interaction of Quarks

CKM Matrix and Its Parametrization

Yukawa Interaction of quarks

Leptonic decays of Mesons

Spin and Parity of Hadronic Currents

Selection Rules for Charged Currents

Semileptonic Decays of Mesons

Neutral Kaons

Processes Involving Baryons

**Global symmetries of standard model**

Accidental symmetries

Approximate symmetries

Chiral symmetries

Anomalies

**Bosons of Standard Model**

Interactions among Bosons

Decay of Gauge Bosons

Scattering of Gauge Bosons

Equivalence Theorem

Custodial Symmetry

Loop Corrections

Higgs Boson

**Hadrons Involving Heavy Quark Flavors**

Charm Quark and Charmed Hadrons

Bottom Quark

Neutral Meson-Antimeson Systems

Top Quark

Quark Masses

Heavy Quark Effective Theory

**CP Violation**

CP Violation and Complex Parameters

Kobayashi-Maskawa Theory of CP Violation

Rephasing Invariant Formulation

CP-Violating Decays of Kaons

Other Signals of CP Violation

Unitarity Triangle

CP Violation and T Violation

Strong CP Problem

**Neutrino Mass and Lepton Mixing**

Simple Extension of Standard Model

Neutrino Oscillation

Majorana Fermions

Consequences of Lepton Mixing

Lepton Number Violation

Models of Neutrino Mass

**Beyond the Standard Model**

Shortcomings of Standard Model

Left-Right Symmetric Model

Grand Unified Theories

Horizontal Symmetry

Supersymmetry

Higher Dimensional Theories

String Theory

**Appendices**

A Units and Constants

B Short summary of particle properties

C Timeline of major advances in particle physics

D Properties of spacetime

E Clebsch-Gordan co-efficients

F Dirac matrices and spinors

G Evaluation of loop integrals

H Feynman rules for standard model

I Books and other reviews

J Answers to selected exercises

**Index **

## Reviews

"… a pedagogical, thorough, and enjoyable introduction to this fascinating subject. … a carefully written textbook on the Standard Model in the post-LHC era, at the level of a graduate-level course. … Theorists and phenomenologists with an interest in particle physics would also do well to acquire a copy. … The biggest strength of this book is its pedagogical clarity. … Apart from the pedagogical value for novices, the later chapters of the book are interesting for active high-energy physicists as well … as a textbook, Palash Pal’s tome on particle physics is accessibly written for serious beginning students, and is a great addition to the bookshelves of seasoned scientists interested in the phenomenological foundations of the Standard Model."

—Current Science, April 2015