CFU
6
Length
14 Weeks
Semester DD
Second
Background. The natural radioactivity . Scattering experiments. Cross sections. Absorption coefficient, attenuation length and mean free path. Total cross section, elastic, inclusive and exclusive. Luminosity and cross section for experiments with crossed beams. Differential cross sections . The atomic models and the Rutherford experiment. The cross section of Rutherford. The proton and nuclear transmutations. The discovery of the neutron. General properties of nuclei. Isotopes , isotonic, isobaric nuclei. Size of atoms, nuclei and particles. Form factors. The size and shape of the nuclei. Nuclear radius. Masses of nuclei. The mass spectrometer; Bainbridge spectrometer. Parity of nuclei. Magnetic Moments of Nucleons. The formalism of the isotopic spin. Binding energy per nucleon. Weizsacker formula . Abundance of nuclides. Stability. Radioactive decays. Law of radioactive decay. Branching ratio. The α decay, the α decay kinematics and elements of the Gamow theory. The β decay and parity violation in weak interactions: the experiment of Wu. The electron capture. The gamma-ray emission. The internal conversion. The isomerism. The radioactive equilibrium. Radioactive families. Relativistic kinematics: the principle of relativity, four vectors and Lorentz transformations; velocities composition: the energy-momentum four-vector; invariant mass; systems of the laboratory and of the center of mass; energy threshold of a reaction ; transformation of the angles ; decay into two bodies. Elements on the nuclear reactions. Energy balance: Q of the reaction. Measurement of the cross section. Reactions to multiple final state. Elastic scattering. Reactions without projectile ( decay ). Nuclear models at interaction strong and at independent particles. Nuclear potential. Drop model. Fermi gas model. Magic numbers. Shell Model. Doubly magic nuclei. The fission and nuclear fusion. Radiation-matter interaction: reduction of intensity and energy loss. Interaction of charged particles with matter : Energy loss by ionization, energy loss by radiation ( Bremsstrahlung ). The range. The phenomenon of multiple scattering. The phenomenon of Straggling energy. Cerenkov effect. Interaction of electromagnetic radiation: Compton scattering, photoelectric effect, pair production. Linear and massive attenuation coefficient. Mean free path. Emivalente and decivalente layers. Interaction of neutrons with matter. Energy lost in the neutron elastic collision. Elements on the detectors for nuclear and subnuclear physics : general characteristics , emulsions, gas detectors , Cerenkov detectors , scintillators , semiconductor detectors . Criteria for the selection of a detector. Elements of particle physics: isotopic spin, strangeness, hypercharge, G-parity, parity, time inversion, charge conjugation, the CPT theorem, Birth of the quark model. Quarks. Particle characteristics. Leptons, mesons, baryons. Color charge. Elements on the standard model of particles and theories of grand unification.
LEARNING OUTCOMES:
The course of study is aimed at providing a first approach to nuclear and subnuclear physics, which will then be further developed in the Master's Course for particle-physics students, but which will in any case be sufficient for a general overview also to all other students whi will deepen other physics topics.
In fact, the course provides a good knowledge of the basic elements of nuclear physics and particle particles.
KNOWLEDGE AND UNDERSTANDING:
Through the course students will acquire knowledge of the fundamentals of elementary particle physics, from nuclear to subnuclear and elementarey-particle dimensions. Based on the knowledge acquired, students will be able to understand the motivations behind many physical phenomena in the microscopic world, from nuclear and particle decays, to scattering interactions, to the creation and discovery of new particles. They will know the conservation laws that are the basis of all the physical processes of the microscopic world and will be able to understand the mechanisms of the fundamental interaction forces that govern the world of elementary particle physics.
APPLYING KNOWLEDGE AND UNDERSTANDING:
Students at the end of the course will be able to apply their knowledge and understanding in order to demonstrate a professional approach in the field of particle physics, both in the nuclear and sub-nuclear fields, either to be studied at accelerators and at natural sources (radioactivity, cosmic rays).
MAKING JUDGEMENTS:
At the end of the course the students will have learned how the scientific method helped in understanding the microscopic world in its historical development, and consequently they will have learned to be rigorous in the formulation of new hypotheses and critical in the analysis of experimental data.
COMMUNICATION SKILLS:
Students will be used, during the course, to interact with the teacher and between them. The scientific discussion is in fact always stimulated during the lessons, and the students can propose topics for discussion or present themselves a topic of interest.
LEARNING SKILLS:
Students will have acquired an understanding of the nature and complexity of the microscopic world, which will be useful to them even if they want to move in other fields.
Moreover they will be able to do autonomous bibliographic searches using sector books, and also to develop familiarity with some specific magazines and with the information available on the internet.