Interpolations of Rosseland-mean opacities for variable X and Z
Abstract
For fixed relative abundances of `metal' atoms, stellar compositions are specified by mass fractions X for hydrogen and Z for metals (the helium mass fraction being Y=1-X-Z). Rosseland-mean opacities depend on temperature, T, density, rho, and chemical compositions. Interpolations in T and rho were discussed in a previous paper. The present paper is concerned with interpolations in X and Z. The opacities are calculated on a grid of (X, Z) values together with information giving derivatives of opacities with respect to X and Z. Opacities for any required value of X and Z can then be obtained using bicubic interpolations. The opacity tables, and codes for making interpolations, are available at the Centre de Donnees de Strasbourg (CDS).*
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- March 1996
- DOI:
- 10.1093/mnras/279.1.95
- Bibcode:
- 1996MNRAS.279...95S
- Keywords:
-
- ATOMIC DATA;
- RADIATIVE TRANSFER;
- ASTRONOMICAL DATA BASES: MISCELLANEOUS