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Stratified NLTE Model Atmospheres for Hot Stars

Published online by Cambridge University Press:  26 May 2016

Stefan Dreizler  and
Sonja L. Schuh
Stefan Dreizler
Affiliation:
Institut für Astronomie und Astrophysik, Universität Tübingen, Sand 1, D-72076 Tübingen
Sonja L. Schuh
Affiliation:
Institut für Astronomie und Astrophysik, Universität Tübingen, Sand 1, D-72076 Tübingen

Abstract

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In most stellar atmosphere models, a homogeneous chemical composition is assumed, which is a good approximation for many stars. With the absence of convection and mass–loss, however, gravitational settling can produce a chemical stratification gradient. Typical examples are white dwarfs. In hot stars this diffusion process is modified by the radiative acceleration, resulting in levitation of ions with large radiative cross sections. The status of our program for self-consistent stratified non-LTE model atmospheres is presented.

Type
Session A. Current Status of Modelling
Information
Symposium - International Astronomical Union , Volume 210: Modelling of Stellar Atmospheres , 2003 , pp. 33 - 43
Copyright
Copyright © Astronomical Society of the Pacific 2003 

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