Optically thick X-ray transfer: the shell game.
Abstract
This paper investigates the radiative transfer of X-rays through a shell that is optically thick to Compton scattering, surrounding a point source of continuum X-rays. The emission and absorption of X-rays due to K-shell transitions of iron are included. The calculations are done in two entirely independent ways: by Monte Carlo simulation and by solving a Fokker-Planck diffusion equation. The emergent spectra agree very well for Thomson depths of at least about 2. The validity is confirmed of the modification to the Fokker-Planck equation of Kompaneets (1957) that is required when the photon energy is large compared with the average thermal energy of the electrons. A procedure is also developed for treating models of compact X-ray sources consisting of incomplete shells.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- June 1978
- DOI:
- 10.1086/156214
- Bibcode:
- 1978ApJ...222..959L
- Keywords:
-
- Electromagnetic Wave Transmission;
- Optical Thickness;
- Radiative Transfer;
- Stellar Atmospheres;
- X Ray Absorption;
- X Ray Sources;
- Atmospheric Models;
- Compton Effect;
- Fluorescence;
- Fokker-Planck Equation;
- Line Spectra;
- Magnetopause;
- Monte Carlo Method;
- Pulsars;
- Astrophysics;
- Radiative Transfer:X Rays