Nuclear and Subnuclear Physics Elements

Module MODULO 1

The student will acquire knowledge of nuclear phenomena, nuclear structure, nuclear interactions, radioactive decays laws and basic concepts related to nuclear collisions. The issues are introduced by describing the phenomenology, the approach used in the measurements and a qualitative and, where possible, quantitative description of the described nuclear phenomena is given. In learning the main theoretical models through which the nuclear structure is studied, the student will also use many concepts acquired in previous courses or which run in parallel with the course in question.

With reference to the Dublin Descriptors, this course contributes to acquiring the following soft skills:

Knowledge and understanding

At the end of the course students will have developed inductive and  deductive reasoning skills.

They will have acquired the main notions underlying the experimentation and phenomenology that led to the description of nuclei and their interactions. They will know the laws and properties of radioactive decays, the structure of nuclei and will know the principles underlying the models that describe the nucleons organization inside the nucleo.

Ability to apply knowledge:

With the knowledge acquired, students will be able to enrich  their knowledge of the topics covered in more advanced courses of their study path.

Autonomy of judgment:

Acquisition of critical reasoning skills

Communication skills

Good skills in tools for the management of scientific information and bibliographic research.

Ability to present an argument orally, with properties of language and appropriate scientific terminology, explaining the motivations and results.

Learning ability

Ability to know how to update their knowledges by reading scientific publications, in Italian or English, in the various fields of physical disciplines, even if not specifically studied during their University studies.

The Course is structured in about 13 weeks, 4 hours of frontal  lectures each week.

During the lesson period a guided tour is carried out at the Laboratori Nazionali del Sud-INFN Catania, during which the activities carried out by researchers in the field of Nuclear Physics are illustrated, also in connection with research in collaboration with Universities and Research Institutes Italian and Foreign.

Essential knowledge: General Physics, Derivatives, Integrals, Differential Equations.

Prerequisites for the IFNS exam are the the Analisi 1, Fisica 1, Fisica 2 exams.

The duration of the course is  about 13 weeks. For each week there are 2 lectures, 2 hours each.

Atoms and nuclei: Size and shape. Mass defect and  Nuclear binding energy . Weisszacher formula. Nuclear Instability in alpha-decay, beta-decay and  Spontaneous Fission. (1^stweek)

Decays: The radioactive decay law. Half-life. Multimodal decays. The production of radioactive material. Sequential decays. Transition rate. 14C dating method. ( 2^ndweek)

Alpha decay: Coulomb barrier penetration. Gamow factor. Angular momentum barrier. Decay schemes involving alpha-particle emission. Geiger-Nuttal formula. Schrodinger equation in polar coordinates. Angular momentum conservation. (3^rd week)

Nuclear Model: The nuclear binding energy. The liquid drop model. Fermi gas model.  Shell model. Nuclear energy levels. Wood-Saxon potential. Spin-orbit interaction. Magic numbers. Splitting of energy levels. (4^thweek) . Bound and virtual levels. Excited states. Spin and parity. Residual interaction in shell model and pairing. (5^thweek)

Nuclear spin and Moments: Nuclear spin. Magnetic and electric Moments. Bohr magneton. Nuclear magneton. Schmidt lines. (6^thweek). Multipole electric moment. Electric Quadrupole moment and  deformed Nuclei. Rotational and vibrational bands. Nilsson levels. (7^thweek)

Beta decay: Energy release in beta decay. Golden Rule n.2. Fermi Theory. Angular momentum and parity selection rules. Fermi (F) and Gamow-Teller (G-T) allowed transitions. Forbidden decays. (8^thweek) .  Beta spectrum, end-point. Kurie-plot. (9^thweek)

Gamma decay: Energetics of gamma decay. Classical electromagnetic radiation. Transition to quantum mechanics. Angular momentum and parity selection rules. (10^thweek) .  Internal conversion. Weisskopf estimation. Metastable states. (11^thweek)

Nuclear collisions: Q-value. 2-body kinematics: study in the laboratory and in the C.M reference frame. Threshold energy. Elastic, inelastic and reaction cross section. Solid angle. (12^th week). Direct and Compound Nucleus reaction mechanisms. Cross section resonances in C.N. mechanisms.  Breit-Wigner formula. Measurement of the experimental differential cross section. (13^th week)

1. H.A.Enge:  Introduction to Nuclear Physics  (Addison Wesley Pub.Co.)
2. J.S.Lilley: Nuclear Physics- Principles and Applications (J.Wiley&Sons, Ltd)
3. B. Povh, K. Rith, C. Scholz, F. Zetsche: Particelle e nuclei. Un' introduzione ai concetti fisici (Bollati Boringhieri)
4. W .S.C. Williams: Nuclear and Particle Physics, (Claredon Press, Oxford)

The exam consists of an oral discussion that focuses on the topics covered in the course.

For the evaluation of the student, the level of knowledge acquired, the expertise achieved and the ability to correlate the different topics covered in the course will be taken into account.

N.B .: The exam relating to Nuclear and Subnuclear Physics Institutions Course  (Mod.1 + Mod.2; 6 + 3 CFU) is unique for the 2 Modules and takes place simultaneously in the presence of the 2 Teachers. The final evaluation for  9 CFU, is also unique.

As a general rule 8 exam sessions are scheduled for  each Academic Year. It is possible to consult the exams calendar on the website of the L30-Physics degree course.

The following list  is not exhaustive,  just a few examples are reported:

Main models for the atomic nucleus. Shell model.

Radioactive decay law. Energetics of alpha, beta decay and spontaneous fission.

Electric and magnetic moments of the nucleon and of the nucleus.

Alpha decay. Tunnel effect.

Beta decay. End-point of beta spectrum .

Gamma decay.

Angular momentum and parity conservation rules in radioactive decays.

Nuclear reactions: exoenergetic and endoenergetic.

Kinematics of nuclear reactions. Experimental cross-section measurements.