Influence of non-adiabatic temperature variations on line profile variations of slowly rotating β Cep stars and SPBs

I. Non-adiabatic eigenfunctions in the atmosphere of a pulsating star

¹ Institut d'Astrophysique et de Géophysique de l'Université de Liège, avenue de Cointe 5, 4000 Liège, Belgium
² Institut voor Sterrenkunde, Katholieke Universiteit Leuven, Celestijnenlaan 200 B, 3001 Heverlee, Belgium

Corresponding author: M.-A. Dupret, dupret@astro.ulg.ac.be

Received: 2 August 2001
Accepted: 31 January 2002

Abstract

In this study, we compute theoretical line profiles of a non-radially pulsating star, taking the non-adiabatic effects into account. These non-adiabatic effects are especially important in the atmosphere, where the spectral lines are formed, and must be accounted for. In this first paper of the series, we present a new treatment of the perturbed thermal and dynamical equations in the atmosphere of a pulsating star. We apply our formalism to the computation of non-adiabatic eigenfunctions in a typical β Cephei star with low order p-modes and in a typical slowly pulsating B star with high-order g-modes.