SOLAR PHYSICS

The course is aimed at providing the student the basic knowledge and the state of the art of the knowledge in Solar Physics: knowledge of the methods used to investigate the solar interior and the solar atmosphere; knowledge of the mechanisms of interaction between the plasma and localized magnetic fields; concept of magnetic reconnection applied to transient phenomena taking place in the solar atmosphere; knowledge of the mechanisms of interaction between the solar magnetized plasma and the Earth magnetosphere in the framework of Space Weather.

Knowledge and understanding: Critical understanding of the most advanced developments in Modern Physics in both theoretical and laboratory aspects and of their interconnections, even in interdisciplinary fields. Adequate knowledge of advanced mathematical and computer tools of current use in the fields of basic and applied research. Considerable mastery of the scientific method, and understanding of the nature and of research methods in Physics. During the course the student will acquire the main concepts underlying the fundamental physical mechanisms that occur in the Sun.

Applying knowledge and understanding: Ability to identify the essential elements of a phenomenon (with reference to the phenomena occurring in the Sun), in terms of order of magnitude and level of approximation necessary, and to be able to make the required approximations. Ability to use the analogy tool to apply known solutions in the field of solar physics to new problems (problem solving) and different astrophysical contexts. Ability to use analytical and numerical mathematical calculation tools and information technology, including the development of software programs.

Making judgments: Ability to convey own interpretations of physical phenomena, when discussing within a research team. Development of a sense of responsibility through the choice of optional courses and the subject of the master thesis.

Communication skills: Communication skills in Italian and English in the advanced fields of Physics. Ability to present one's own research activity or a review topic both to an expert and to an non-expert audience. These skills will be developed in the context of communicating the processes that take place in the Sun.

Learning skills: Ability to acquire adequate tools for the continuous update of one's knowledge and to access specialized literature both in the field of solar physics and in scientifically close fields. Ability to exploit databases and bibliographical and scientific resources to extract information and suggestions to better frame and develop one's study and research activity. Ability to acquire, through individual study, knowledge in new scientific fields.

Teaching is mainly based on lectures (in English). The students will also be invited to attend (on-line) seminars on selected topics of solar physics.

There will also be some practical exercises aimed at learning some techniques used in solar physics, as well as some guided visits to observational infrastructures of INAF - Catania Astrophysical Observatory.

Should the circumstances require online or blended teaching, appropriate modifications to what is hereby stated may be introduced, in order to achieve the main objectives of the course.

Verification of learning will be carried out through an oral final exam. Through questions related to qualifying points of the various parts of the program, the exam is aimed at ascertaining the overall level of knowledge acquired by the candidate, his/her ability to critically address the topics studied and to correlate the various parts of the program.

The final grade will equally match the knowledge shown in the qualitative and quantitative arguments, the critical view of the topics dealt with during the course and the ability to correlate the various parts of the program.

Exams may take place online, depending on circumstances.

The solar interior: core, radiative zone, convective zone. The Standard Solar Model. Nuclear fusion in the solar core. Measure of the solar neutrinos flux. Heliosismology. Oscillations as a diagnostic tool to investigate the inner structure and dynamics of the Sun. The internal solar rotation.

The solar atmosphere:

Photosphere, Chromosphere, Transition Region, Corona. Solar differential rotation.

Telescopes, Instruments and Techniques to observe the Sun:

Techniques of observation of the various layers of the solar atmosphere. Solar telescopes. Spectrographs. Filters. Polarization of light. Spectro-polarimetry.

Magnetic structures in the solar atmosphere:

Active regions, sunspots, prominences, loops, coronal holes. Emergence of magnetic flux in the solar atmosphere. Formation and evolution of active regions. Sunspots: physical and morphologic characteristics. The 11-year cycle of solar activity. The dynamo model. Chromospheric-coronal heating. Solar wind.

Solar eruptive events:

Flares and filament eruptions: observational characteristics and models. Coronal Mass Ejections. Space Weather.

Textbooks:

• H. M. Antia, A. Bhatnagar, P Ulmschneider : Lectures on Solar Physics, Springer Verlag, 2003

• M. Aschwanden : Physics of the solar corona: an introduction, Springer, Praxis Pub. Ltd, 2004

• R. J. Bray, L. E. Cram, C. J. Durrant, R. E. Loughhead : Plasma loops in the solar corona, Cambridge University Press, 1991

• K. R. Lang : The Sun from Space, Springer, 2000

• E. Landi Degl'Innocenti : Fisica Solare, Springer Verlag, 2008

• E. R. Priest : Solar system magnetic fields, Reidel Publ. Co., Dordrecht, 1985

• E. Tandberg-Hanssen, A. G. Emslie : The physics of solar flares, Cambridge University Press, 1988