Photospheres of hot stars. I. Wind-blanketed model atmospheres.
Abstract
Preliminary to an extensive and detailed comparison of improved non-LTE photospheric models with observations of hot stars made with high photometric accuracy, non-LTE stellar atmospheres are constructed which account for the radiation reflected back onto the photosphere by line and electron scattering from the wind. The effects of this 'wind blanketing' on the spectrum and internal structure of the atmosphere are given for an example with an effective temperature T(eff) of 42,000 K, and a wide range of wind density, gravity, and model assumptions. Particular attention is given to the problem of determining T(eff). Careful analysis of methods currently used to determine T(eff) from continuous flux distributions, with and without interferometric angular diameters, shows them to be unreliable in practice. Line profiles continue to provide a legitimate means of determining T(eff) but only when their dependence on gravity and mass loss is included. For the more luminous OB stars spectral classification is truly three-dimensional, with the mass loss rate, gravity, and effective temperature all playing nearly equal roles in specifying the observed spectrum.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 1985
- DOI:
- 10.1086/163297
- Bibcode:
- 1985ApJ...294..286A
- Keywords:
-
- Hot Stars;
- Photosphere;
- Stellar Models;
- Stellar Spectra;
- Stellar Winds;
- Albedo;
- Early Stars;
- Stellar Atmospheres;
- Stellar Mass;
- Thermodynamic Equilibrium;
- Astrophysics