Radiation Transfer and Stellar Atmospheres

This course covers the basics necessary for a good understanding of the physics of atmospheres and stellar winds. The essential elements of radiation transfer theory are covered, both at ETL (local thermodynamic equilibrium) and outside ETL, as well as the description of the gas (equation of state) and its interaction with the radiation field (opacities). Modern models and simulations are presented with their application to the determination of stellar parameters, in particular the chemical composition, via spectroscopy. The different types of stellar winds (pressure, radiative, hybrid) are described via theories compared to observations.

To provide a fundamental foundation in radiative transfer to address most astrophysical problems

Acquire the basics of stellar atmospheric physics in order to be able to approach specialized publications in the field

To know the essential theories of stellar winds, and the related mechanisms

Apply this knowledge to perform calculations, estimate orders of magnitude, or test a theory.

To know the existence of the emblematic numerical codes of simulation of the atmospheres and their field of application

Recommended Prerequisites:

Basics of astrophysics, quantum mechanics, atomic physics, statistical physics

Continuous control integral

Advanced radiative transfer: ETL, off-ETL, line formation, atomic processes, radiative equilibrium, gray atmosphere

Stellar atmospheres: physical equations and ingredients, structure, hydrostatic atmospheres, convection, 3D radiative hydrodynamic simulations, diagnostics

Stellar spectroscopy: two-level atoms, line broadening, determination of the chemical composition of atmospheres

Stellar winds: solar wind, radiative winds of hot stars, hybrid winds of red giants