Prof. F. Berrilli
Space Weather
(S3, elective, 6 ECTS)
Learning Outcomes:The course of study is aimed at providing an advanced preparation on Solar Physics, on the physical processes linked to the Sun-Earth interactions and about the phenomenology connected to the Sun and the heliosphere. In particular, deepening specialized topics of recent research in the field of solar activity and Space Climate / Weather will be studied. objectives include advanced knowledge of classical and quantum physics, plasma physics and, possibly, some stellar astrophysics topics. In any case, the course is designed in a modular and self-consistent manner.
Knowledge and Understanding:
Students must learn the basic physics and phenomenology necessary to understand the modeling applied to the Sun and to the Sun-Earth interaction processes, to the Space Climate / Weather and to the analysis of solar and spatial data obtained from experiments from space or ground-based.
Applying Knowledge and Understanding:Students must have adequate skills and tools for communication and information management and must be able to access and understand the scientific bibliography on the subject.
PrerequisitesGeneral physics, Quantum Physics
ProgramBasics: Sun facts, basic concepts of solar structure (scaling arguments), pressure, temperature and luminosity. Solar neutrino problem: solar energy source, the spectrum of solar neutrinos, experiments (Homestake, Gallex, SAGE, Super-Kamiokande, SNO), neutrino oscillations. Solar Spectrum: interpreting solar spectrum, radiative transfer basics, and limb darkening in a resolved star, real atmosphere models, second solar spectrum, solar Balmer spectrum and H-/H ratio. Stellar turbulent convection: Rayleigh-Bénard convection, instability criteria (Ledoux and Schwarzschild), the adiabatic temperature gradient, the convection zone, new paradigm of stellar turbulent multiscale convection, regimes of magneto-convection, convective collapse. Helioseimology: solar oscillations, pressure and gravity waves, p-modes and g- odes, propagation of gravity waves, Brunt-Väisälä frequency, helioseismology results (solar rotation profiles, torsional oscillations, tachocline), time-distance helioseismology. Stellar global dynamo: solar global dynamo, solar cycles, butterfly diagram, Hale’s polarity law, Joy’s law, the reversal of magnetic field, ephemeral regions (EPRs), the Babcock-Leighton dynamo, MHD regimes, plasma flows over the Sun, small magnetic element advection, solar activity and small scale dynamics, exoplanets detection and stellar noise: the solar lesson. Solar Drivers of Space Weather: the connection photosphere-chromosphere-Corona, coronal holes, flares, Coronal Mass Ejections (CMEs), solar wind, Co-rotating Interacting Regions CIRs), the Interplanetary Magnetic Field (Parker Spiral). Flare forecasting algorithms: forecast M-and X-class solar flares, photospheric magnetic field proxies and active regions parameters, active region parameter formulae, MOTH telescope and 3d solar magnetic field. Sun and Earth’s climate: solar influence on climate, the faint young Sun paradox, Total and Spectral Solar Irradiance, solar magnetic variability, Milankovitch cycles and Earth’s orbit (eccentricity, obliquity, precession), solar modulation of Cosmic Rays, stratospheric ozone and solar spectral variability.
Description of how the course is conductedClassroom lectures, also inviting experts from specific fields for short seminars/lectures.. The attendance and participation in the class and laboratory is not mandatory. However, the nature and complexity of the matter make the attendance strongly recommended.
Description of the didactic methodsPowerPoint presentations.
Description of the evaluation methodsThe exam consists in the discussion of a presentation, related to a course topic agreed with the student, and questions related to the class syllabus.
Adopted TextbooksThe Sun: an introduction – M. Stix Fundamentals of Solar Astronomy – A. Bhatnagar and W. Livingston The Sun and Space Weather – A. Hanslmeier
Recommended readingsThe lessons of the course are distributed to students, as pdf files, together with review papers on topics of particular interest to the students.