General astrophysics 1100-3A12
Program:
1. Field of radiation: intensity, mean intensity, flux, density and pressure of radiation. Black-body. Kirchhoff law.
2. Atomic gas. Equation of state. First thermodynamic principle. Thermodynamic processes in gases. Photon gas. Maxwell and Boltzmann distributions. Saha equation. Mixture of gases: dependence between electron and total gas pressure. Equation of state of degenerate gas.
3. Interaction of matter with radiation. Macroscopic coefficients of extinction and emission. Equation of radiative transfer and its formal solution. Atomic processes of absorption and emission. Einstein coefficients. Bound-bound, bound-free, free-free processes and scattering.
4. Transport of energy in stars: radiation and convection equilibria. Diffusion approximation. Rosseland mean extinction coefficient. Criterium of convective stability. Mixing length theory.
5. Basic equations of stellar structure: conservation of mass, hydrostatic equilibrium, energy conservation, energy transport, boundary conditions.
6. Variable stars: classification, description of selected types of variable stars.
7. Stellar pulsations. Radial and non-radial oscillations. Equation of motion. Period-mean density relation. Pulsation constant. Period-luminosity-color relation. Kappa mechanism of pulsation. Instability strips on the HR Diagram. Baade-Wesselink method.
8. Double stars: classification, orbit elements, mass function, Lehmann-Filhes method.
9. Effects of the radiation pressure: Eddington brightness limit, radiative acceleration, radiative winds.
10. Ionization equilibrium in rarefied gas: Equation of statistical equilibrium, HII zones, Stroemgren spheres.
Main fields of studies for MISMaP
Prerequisites (description)
Course coordinators
Assessment criteria
Oral exam
Bibliography
1. D. Mihalas: Stellar Atmospheres
2. A. Unsoeld: Physik der Sternatmosphaeren
3. L. Aller: Atoms, Stars and Nebulae
Additional information
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