# ELEMENTARY PARTICLE PHENOMENOLOGY

- Overview
- Assessment methods
- Learning objectives
- Contents
- Full programme
- Bibliography
- Teaching methods
- Contacts/Info

Nuclear and sub-nuclear physics with exercise classes

Quantum physics (Modules 1 and 2)

Electromagnetism (Modules 1 and 2)

The course examination takes the form of a single final oral discussion. In order to ascertain the expositional abilities in elementary particle physics phenomenology and the level of understanding of the subject, students are asked to make a previously prepared oral presentation. During and after the presentation, questions are posed with the aim of testing the ability to reason on the subject under discussion and to verify the level of understanding of the major topics covered during the lessons, as well as the studentâ€™s analytical and computational skills.

The purpose of the course is to provide students with an introduction to the phenomenology of elementary particle physics, defined as the interaction between the two main spheres of activity: on the one hand, the development of the theory that describes the physical world at the sub-nuclear level and, on the other, the experimental work aimed at verifying the validity of this description and at discovering possibly new, as yet unknown and often unexpected aspects. Students will thus acquire a state-of-the-art knowledge of both theoretical and experimental elementary particle physics, together with an understanding of the mechanisms and motivations that led up to the current theoretical and experimental scheme. They will also acquire the necessary skills to analyse fundamental interactions both from the point of view of conservation and symmetry laws and with regard to kinematics and the underlying dynamics.

â€¢ Symmetries

> parity violation in the weak interaction

> the V â€“ A formulation of weak currents

> Cabibbo theory

> the GIM mechanism and the CKM matrix

> CP violation in the Standard Model

> the CPT theorem

â€¢ Hadronic Physics

> Gell-Mann's quark theory âˆ’ SU(3)

> Feynman's quarkâ€“parton model

> the strong interaction âˆ’ QCD

> DIS and ep machines

> asymptotic freedom & confinement

> the "new" particles

â€¢ Cosmic Rays and First Discoveries

> e+eâ€“ machines

> resonance production & Breitâˆ’Wigner

> discovery of the c and b quarks

> discovery of the tau lepton

> pp machines

> discovery of WÂ±, ZÂ° and the t quark

â€¢ Elementary Particles and Fundamental Forces

> the need to extend the Fermi theory of weak interactions

> the spontaneous breaking of symmetries (the Higgsâˆ’Kibble mechanism)

> B-meson physics

> the discovery and measurement of CP violation

> proton decay

> the Standard Model

â€¢ General Issues

> neutrino masses, oscillation and mixing

> GUTs

> SuSy

> beyond the 4 dimensions

> beyond the Standard Model

The first part of the course examines the question of symmetries.

Parity violation in weak interactions through its effect in nuclear beta-decay is discussed in detail, leading to the universal V â€“ A formulation of weak currents and also to Cabibbo theory. The consequent difficulties owing to the non-observation of certain neutral-kaon decays are shown to lead to the GIM mechanism and the prediction and discovery of the c-quark, while the requirement that CP (or T) be violated is shown to lead to the formulation of the CKM matrix and the prediction of further quarks.

The section on hadronic physics first deals separately with the two approaches to the sub-structure of the nucleons: Gell-Mann's quark theory and Feynman's parton model. The subsequent unification of the two approaches is then developed through the invention of quantum chromodynamics (QCD). In particular, the description afforded of deeply inelastic electronâˆ’proton scattering is presented in detail. The notions of asymptotic freedom and confinement within the quarkâˆ’parton model complete the description of the strong interaction.

We then move on to cosmic rays and first discoveries of new particles. The natural progression then continues with the early e+eâ€“ machines and the discovery of the c and b quarks, followed by the tau lepton. Finally, the remaining discoveries of the WÂ± and ZÂ° bosons and of the t-quark at protonâˆ’proton and protonâˆ’antiproton machines are described.

Having examined the individual interactions (the weak and strong nuclear forces) we present the unified picture, such as it is, of the elementary particles and fundamental forces that describe their interactions. The path to the Standard Model (SM) of elementary particle physics via the spontaneous breaking of symmetries (the Higgsâˆ’Kibble mechanism) is traced through to the present description of the electro-weak interaction. Various related topics, such as D- and B-meson physics, the discovery and measurement of CP violation, proton decay and the implications of Standard Model in general are briefly discussed.

To conclude we examine some new and/or unexplained aspects of modern particle physics. The topics touched upon include: neutrino masses, oscillation and mixing, GUTs, SuSy, beyond the 4 dimensions and beyond the Standard Model.

Notes will be made available online via E-learning platform https://elearning.uninsubria.it/.

Suggested supplementary (not compulsory) texts:

P.G. Ratcliffe "An Introduction to Elementary Particle Phenomenology" (IoP, 2014);

D. Perkins, "Introduction to High Energy Physics" (CUP, 2000);

F. Halzen & A. Martin, "Quarks and Leptons" (Wiley, 1984);

Povh et al., "Particles and Nuclei" (Springer, 1995).

Conventional blackboard teaching, including exercise classes in the lecture room for a total of 64 hours.

Office hours:

by appointment (contact philip.ratcliffe@uninsubria.it)