Electroweak Symmetry and Its Breaking

Contents
Preface
1. Introduction
	1.1 Symmetries
	1.2 The Cast
	Suggested Reading for Chapter 1
2. Electroweak Interactions
	2.1 Helicity, Chirality and P-Parity
	2.2 Why Weak Interactions are Weak?
	2.3 The Recyclable SU(2) Group
	2.4 Neutral Currents
	2.5 Add Photons to Taste
	2.6 Combining Weak and Electromagnetic Interactions
	2.7 Feynman Rules
	2.8 Properties of W and Z Bosons
	2.9 Asymmetries in e+e− Annihilation
	2.10 Building the Electroweak Lagrangian
	2.11 Gauge Boson Helicity and Mass
	Suggested Reading for Chapter 2
3. Electroweak Symmetry Breaking
	3.1 Scalar Field Doublet and Its Quantum Numbers
	3.2 The Higgs Potential
	3.3 Generating Gauge Boson Masses
	3.4 Generating Fermion Masses
	3.5 Higgs Boson Mass and Self-Interaction
	3.6 Excitation Around the Minimum — Higgs the Particle
	3.7 Summary of Theory Predictions
	Suggested Reading for Chapter 3
4. Higgs Boson Production and Decay
	4.1 Higgs Decays
		4.1.1 Higgs boson decay to fermions
		4.1.2 Higgs boson decay to gauge bosons
		4.1.3 Higgs boson decay branching ratios as a function of its mass
	4.2 Higgs Production in e+e− Collisions
	4.3 Higgs Production in Proton–Antiproton Collisions
	4.4 Higgs Production in Proton–Proton Collisions
	Suggested Reading for Chapter 4
5. Higgs Boson Discovery
	5.1 Indirect Constraints and Limits from Direct Searches
	5.2 Higgs Boson Decay to Two Photons
	5.3 Higgs Boson Decay to a Pair of Z Bosons
	5.4 Après Discovery
	Suggested Reading for Chapter 5
6. Higgs Boson Properties
	6.1 Spin and Parity: Is it Higgs?
	6.2 Mass
	6.3 Width
	Suggested Reading for Chapter 6
7. Couplings
	7.1 Separating Production Channels
	7.2 The Kappa Framework
		7.2.1 Effective loops
		7.2.2 Constraints on κ parameters
	7.3 h → WW
	7.4 The Yukawa Couplings of Fermions
	7.5 tth Production
	7.6 Physics Near the tt Threshold
	7.7 h → Invisible
	7.8 Combined Results
	Suggested Reading for Chapter 7
8. Future Measurements
	8.1 Accessing Higgs Couplings to the Second-Generation Fermions
		8.1.1 h → μμ
		8.1.2 h → cc
	8.2 Higgs Self-coupling — Mapping the Higgs Potential
	8.3 Considerations for Future Colliders
	8.4 Overconstraining the Standard Model
	Suggested Reading for Chapter 8
9. Scalar Fields Beyond the Standard Model
	9.1 Why the Standard Model is not Complete
	9.2 The Hierarchy Problem and Fine Tuning
	9.3 Multiple Scalar Doublets
	9.4 Supersymmetry and Its Breaking
		9.4.1 Supersymmetry breaking, gravity and EWSB
	Suggested Reading for Chapter 9
10. Putting Things in Perspective
	10.1 Cosmological Role of Scalar Fields
	10.2 On the Philosophical Meaning of Gauge Invariance
	Suggested Reading for Chapter 10
A Relevant Reviews
	A.1 Kinematics
		A.1.1 Covariant notation
		A.1.2 Observed events, backgrounds, significance
		A.1.3 Cross section
		A.1.4 Decay widths
	A.2 Spin 1/2 Particles
		A.2.1 Properties of the SU(2) symmetry group
		A.2.2 Helicity and spinors
		A.2.3 Dirac equation and Dirac spinors
		A.2.4 Axial and vector properties of γ matrices
		A.2.5 Chirality operator
	A.3 Spin 1 Particles
		A.3.1 Photons
		A.3.2 Massive vector bosons
	A.4 Some Basics on Lagrangians
		A.4.1 Noether’s theorem
	A.5 Electromagnetic Interactions
		A.5.1 Currents and electric charge
		A.5.2 QED Lagrangian
	A.6 Summary of Electroweak Interactions
		A.6.1 Coupling constants
		A.6.2 Masses
	Suggested Reading for Appendix A
List of Figures with Credits
Index