87977 - Subnuclear Physics

Academic Year 2023/2024

Learning outcomes

At the end of the course the student will know the conceptual foundations of subnuclear physics. He/she will be introduced to the notions of symmetry principles and groups and their mathematical formalism, in order to describe the gauge theories (QED, QFD and QCD) of the Standard Model as well as its possible extensions.

Course contents

Module 1: Continuous symmetries and Noether theorem; global and local gauge theories, Abelian (electromagnetism) and non Abelian (Yang-Mills theory of isospin) gauge theories. – – Gauge theory of electromagnetic interactions (QED) and U(1)-e.m. symmetry group; Dirac equation, helicity and chiral representation, introduction to Feynman diagrams and rules (propagators, vertex factors, invariant amplitude).Spontaneous symmetry breaking (SSB), Nambu-Goldstone theorem, Brout-Englert-Guralnik-Hagen-Higgs-Kibble mechanism and Higgs boson. – Weak interactions, gauge theory of electroweak interactions (QFD) and SU(2)-left x U(1)-weak-hypercharge group. – Standard Model, flavour mixing, Cabibbo angle, Glashow-Iliopoulos-Maiani mechanism, Kobayashi-Maskawa matrix, CP violation. – Precision tests of the Standard Model. – Introduction to renormalization and running, to supersymmetry (SUSY) and grand unification (GUT). – The contents of the course will be accompanied by the discussion of "key measurements" on the experimental side.

Module 2: Gauge theory of colour interactions (QCD) and SU(3)-colour group; introduction to quark confinement. – Deconfinement and chiral symmetry breaking. – Key examples and experimental measurements.

Readings/Bibliography

C. Quigg, Gauge Theories of the Strong, Weak and Electromagnetic Interactions (Addison-Wesley Publishing Company) – I.J.R. Aitchison, A.J.G. Hey, Gauge Theories in Particle Physics, volume I: From Relativistic Quantum Mechanics to QED; volume II: QCD and the Electroweak Theory (Institute of Physics Publishing) – F. Halzen, A.D. Martin, Quarks and Leptons: an Introductory Course in Modern Particle Physics (John Wiley & Sons) – R.Cahn and G. Goldhaber, The Experimental Foundations of Particle Physics, Cambrige University Press – D. Griffiths, Introduction to Elementary Particles (Wiley-vch) – S. Coleman, Selected Erice Lectures Aspects of Symmetry (Cambridge University Press) – A. Bettini, Introduction to Elementary Particle Physics (Cambridge University Press) – R.H. Mohapatra, Unification and Supersymmetry: the Frontiers of Quark-Lepton Physics (Springer-Verlag) – I. Aitchison, Supersymmetry in Particle Physics (Cambridge University Press)

Teaching methods

Lectures (48 hours), that may also include a number of topical seminars

Assessment methods

Presentation, at least 7 days before the oral examination, of a written essay on a topic assigned by the teacher, of no more than 25 pages.

Subsequent oral examination with presentation via slides of the essay, during which questions will be asked by the teacher not only on the topic presented but, in general, on the various contents of the course.

Teaching tools

Slides and video projector

Office hours

See the website of Silvia Arcelli

See the website of Francesca Bellini