80327 - Nuclear and Subnuclear Physics (M-Z)

Learning outcomes

The student acquires and consolidates the basic concepts on nuclear physics and aprticle physics with applications and exercises.

Course contents

Nuclear Physics

Rutherford’s experiment and the discovery of the nucleus. Definition of cross section: total and differential, in one or more variables. Units of measurement in nuclear and subnuclear physics. Properties of microscopic particles.

The nucleus and its constituents. Nuclear radius; differential cross section of neutrons on nuclei.

Nuclear binding energy: the concept of binding energy and experimental data. The liquid-drop model of the nucleus: volume, surface, Coulomb, asymmetry, and pairing terms; the Weizsäcker formula.

Review of quantum mechanics: wave function, energy and momentum, orbital and spin angular momentum, addition of angular momenta. Identical particles, symmetry and antisymmetry of the wave function, spin-statistics theorem.

Decays, secular equilibrium, and an introduction to radiation protection.

Nuclear magnetic moments. The Landé factor.

The deuteron as the simplest nucleus. The Fermi gas model.

The nuclear shell model: nuclear potential, separation energies, the Woods-Saxon potential, spin-orbit interaction in electromagnetism, spin-orbit interaction in the strong interaction between nucleons, and comparison with experimental data.

Reactions and decays. Introduction to fusion and fission. Alpha decay: the Geiger-Nuttall law. Beta decay: Fermi’s golden rule and calculation of the spectrum. Implications for the neutrino mass.

Elementary Particle Physics

An overview of the Standard Model: the concept of particle, particles and antiparticles, and flavour quantum numbers; leptons, quarks, and hadrons; electromagnetic, weak, and strong interactions; parameters of the Standard Model.

How particles are measured. Ionization and the Bethe-Bloch formula.

Cosmic rays. Discovery of the muon and the pion.

General aspects of the Standard Model. Estimation of the relative strength of interactions; the emergence of the concept of a quantized field: the Klein-Gordon equation. Introduction to the Dirac equation and the discovery of antimatter.

Discrete symmetries: parity and its violation. Madame Wu’s experiment. Charge conjugation. Neutrino helicity.

The description of natural interactions. Real and virtual quanta. The Yukawa potential. Relativistic Fermi’s golden rule. Feynman diagrams. A heuristic approach to estimating Feynman diagrams. Feynman diagrams as a perturbative theory. Running of the constants.

Cross sections and decays. The Breit-Wigner distribution. Resonances. Universality of charged-current weak interactions.

Strong interactions. The negative omega baryon, colour charges and gluons, flavour structure of strong interactions, isospin, asymptotic freedom and confinement. Flavour quantum numbers. The quark model of hadrons: hadron structure, masses, spin, and electric charges; mesons, baryons, and antibaryons. The quark model of mesons: mesons with light quarks, excited mesonic states, decay patterns, and the OZI rule. The quark model of baryons.

The weak interaction of quarks. The Cabibbo mechanism. Absence of FCNC. The GIM mechanism. The CKM matrix.

Electroweak unification: introduction to V-A theory. Chirality and helicity. Discovery of neutral currents. Discovery of the W and Z bosons.

Readings/Bibliography

Lecture notes made available on the platform virtuale.

Nuclear and Particle Physics - an introduction, B. R. Martin and G. Shaw. 

A Modern Primer in Particle Physics - F. Terranova

Introductory Nuclear Physics, K. Krane, Ed. John Wiley and Sons.

Introduction to elementary particle physics, A. Bettini, Ed. Cambridge University Press.

Teaching methods

Lectures on electronic devices and blackboard. Videos made available on the virtual learning environment. Exercises. 

Assessment methods

General Information About the Exam

The exam consists of a written test and an oral examination.

There are six exam sessions per academic year: three in the winter session, two in the summer session, and one in the autumn session. No extraordinary exam sessions are scheduled.

In order to take the written and oral exams, students must register through the AlmaEsami platform.

The written test consists of two parts. The first part is taken in person on a computer and consists of 10 short-answer questions, graded automatically by the system. Passing this test grants access to the second part, which consists of two problems to be solved on official exam sheets.

The grade obtained in the written test is valid only for the exam session in which it is obtained. The oral examination must be taken in the same exam session as the written test.

The final grade is approximately the average between the written-test grade and the oral-exam grade. A grade of 30 cum laude is counted as 31/30.

If a student fails the oral examination or rejects the grade, the written test must be repeated.

Teaching tools

Learning material provided by the lecturer on the virtual learning environment. 

Office hours

See the website of Iacopo Vivarelli