Radiative accelerations in stellar atmospheres

¹ Laboratoire d'Astrophysique Extragalactique et de Cosmologie, CNRS–(UMR 8631), Observatoire de Paris, Université Paris 7, DAEC, Observatoire de Meudon, 92195 Meudon Cedex, France
² Département de Physique et d'Astronomie, Université de Moncton, Moncton, N.-B., Canada E1A 3E9
³ Department of Physics and Astronomy, University of Georgia, Athens, GA 30602-2451, USA
⁴ Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks, Room 131, Norman, OK, 73019-0225 USA

Corresponding author: A. Hui-Bon-Hoa, alain.hui@obspm.fr

Received: 16 August 2001
Accepted: 22 October 2001

Abstract

We present calculations of radiative accelerations obtained with the general purpose model atmosphere code PHOENIX. The accelerations are computed simultaneously for all the elements He–Ga; Kr–Nb; Ba; La, using the opacity sampling method. The calculations are mainly performed with the LTE approximation. Tests are made to evaluate the influence of non-LTE effects and the validity of the radiative flux obtained through the diffusion approximation. It is shown that the abundances supported in the atmospheres of HgMn and He-weak stars are generally consistent with those observed.