Stellar atmospheres

The radiation field is considered along with the equation of transfer, the grey atmosphere, absorption cross-sections, the equations of statistical equilibrium, and the solution of the transfer equation. A description of model atmospheres is presented, taking into account the classical model-atmospheres problem, Local Thermodynamic Equilibrium (LTE) radiative-equilibrium models, convection and models for late-type stars, the results of LTE model-atmosphere calculations for early-type stars, non-LTE radiative-equilibrium models for early-type stars, extended atmospheres, and semiempirical solar models. Attention is given to the line absorption profile, classical treatments of line transfer, non-LTE line transfer in the case of the two-level atom and the multilevel atom, line formation with partial frequency redistribution, radiative transfer in moving atmospheres, the equations of hydrodynamics for an ideal compressible fluid, coronal winds, radiation hydrodynamics, and radiatively driven winds.