Radiation Hydrodynamics in Pulsating Stars

Abstract

The topic of this review encompasses all aspects of pulsation theory, for the radiation field is never negligible in stellar stability problems, on the contrary, it is usually the primary destabilizing factor through its thermal effects, and modifies the envelope structure and stability through its dynamic effects. The impossibility of a general review of such a broad topic is apparent, and I will concentrate in this talk on the most striking aspect of pulsating stars: nonlinear effects in the outer layers. To focus the discussion, I will address primarily two problems of current interest: shock development driven by the pulsating velocity field, and time dependent turbulence in the ionization zones. The emphasis will be on methodology rather than specific problems and developments.