Low temperature mean opacities for the carbon-rich regime

Autor(en)

Michael Lederer, Bernhard Aringer

Abstrakt

Asymptotic Giant Branch (AGB) stars undergo a change in their chemical composition during their evolution. This in turn leads to an alteration of the radiative opacities, especially in the cool layers of the envelope and the atmosphere, where molecules are the dominant opacity sources. A key parameter in this respect is the number ratio of carbon to oxygen atoms (C/O). In terms of low temperature mean opacities, a variation of this parameter usually cannot be followed in stellar evolution models, because up to now tabulated values were only available for scaled solar metal mixtures (with C/O~=0.5). We thus present a set of newly generated tables containing Rosseland mean opacity coefficients covering both the oxygen-rich (C/O1) regime. We compare our values to existing tabular data and investigate the relevant molecular opacity contributors.

Organisation(en)

Institut für Astrophysik

Seiten

11-18

Anzahl der Seiten

8

DOI

https://doi.org/10.1063/1.2916953

Publikationsdatum

2008

ÖFOS 2012

1030 Physik, Astronomie

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/a198ae50-497d-4c35-ab3e-a2984239cbd8