B016315 - ASTROPHYSICS

Italian

Stellar interiors: hydrostatic equilibrium, equation of state, radiative equilibrium, opacity, Rosseland mean, thermonuclear reactions, convection, mixing length. Standard solar model, neutrino, solar oscillations. Stellar spectra and evolution. Stellar atmospeheres, radiative transfer, the grey atmosphere. Boltzmann and Saha equations. Celestial objects masses: Jeans, Eddington limit, Chandrasekhar, minimum of star, planets. Two-bodie systems, Roche lobes, accretion disks. Tidal forces.

E. Landi Degl'Innocenti, "Fisica Solare", Springer Italia.
E. Landi Degl'Innocenti, "Spettroscopia Atomica e Processi Radiativi", Springer Italia.
Notes of the lectures on the arguments not covered in the mentioned books are available.

Fundamental knowledge in non-relativistic astrophysics,. Basic competences of the physiscist relatively to astrophysics. Skills in working out physical models of astrophysical objects and verifying their validity, in guessing structural analogies among different phenomenological scenarios.

Recommmended courses: all courses of the "Corso di Laurea" in Physics and Astrophysics.

9 CFU, 80 hours of lecturing, including 15 hours of exercises.

Students can consult the teacher on Tuesdays from 16:30 tro 17:30 (after the lecture).

Oral test

Stellar interiors: hydrostatic equilibrium, equazione of state, rcorrections to the equation of state due to electrostatic interactions and to degeneracy, radiative equilibrium, opacity, Rosseland mean, Thomson scatteing, free-free and bound-free transitions, Kramers equations, thermonuclear reactions, nuclear rates according to the Gamow model, convection, Schwarzschild criterion for stability against convection, mixing length theory. The standard solar model, neutrino astrophysics, Davis experiment, non-standard solar models, further experiments of neutrino capture, neutrino oscillations, solar oscillations, waves in a stratified medium, cut-off frequency, Brunt-Väisälä frequency, p-modes and g-modes. Spectral types, stellar evolution, Hayashi tracks, main sequence, red giants branch, final stages of stellar evolution. Interpretation of stellar spectra, Theory of stellar atmospeheres, radiative transfer, optical depth, Eddington-Barbier approximation, the grey atmosphere. Classical atomic theory, damping, Doppler effect, Voigt function, spectral line formation, equivalent width. Boltzmann equation and Saha equation. Masses of celestial objects: Jeans mass, Eddington limit, Chandrasekhar mass, minimum mass of a star, mass-luminosity relation. Rigidity of solid matter, mass of planets. Astrophysics of two-bodies systems, Kepler laws, Lens vector, Roche lobes, Lagrangian points, Keplerian accretion disks, tidal forces, precession.