On the κ-mechanism and the multi-dimensional Eddington approximation.
Abstract
To consider the possibility of a κ-like overstability mechanism as the driving force of solar modes of oscillation requires a theoretical description of the interaction between the hydrodynamics of the motion and the radiative energy transport. The aim of this paper is to answer the question of whether or not the frequently-used multi-dimensional Eddington approximation is suitable for such purposes. It is found that Eddington's approximation is generally adequate for giving account of the radiative damping effects of Planck function fluctuations, while it is in gross disagreement with the exact results with respect to the radiative transfer effects of opacity fluctuations. Therefore, it is concluded that its use should be avoided, when investigating κ-like excitation mechanisms for nonradial stellar modes of oscillation.
- Publication:
-
Seismology of the Sun and Sun-Like Stars
- Pub Date:
- December 1988
- Bibcode:
- 1988ESASP.286...11T
- Keywords:
-
- Eddington Approximation;
- Hydrodynamics;
- Solar Oscillations;
- Energy Transfer;
- Opacity;
- Radiative Transfer;
- Solar Physics;
- Radiative Transfer: Stellar Oscillations;
- Solar Oscillations: Models;
- Solar Oscillations: Radiative Transfer