Neutron star model atmospheres - a comparison with MXB 1728-34.
Abstract
A detailed comparison between the X-ray spectra calculated for model atmospheres in neutron stars and the observed spectra of X-ray bursts is presented. Comptonization and free-free absorption and emission processes are taken into account, as are the effects of iron in its last three states of ionization. Two types of model are formulated, a constant density atmosphere, and an atmosphere in approximate hydrostatic equilibrium. General correction formulas between color temperature and effective temperature are obtained by folding the model spectra through the EXOSAT detector response. The models have been fitted to X-ray burst data obtained with EXOSAT from the source MXB 1728-34. It is shown that it is possible simultaneously to fit a sub-Eddington burst luminosity, a neutron star radius consistent with current equations of state, and a distance, in agreement with optical estimates.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- July 1986
- DOI:
- 10.1093/mnras/221.2.409
- Bibcode:
- 1986MNRAS.221..409F
- Keywords:
-
- Atmospheric Models;
- Neutron Stars;
- Stellar Atmospheres;
- Stellar Models;
- X Ray Sources;
- Black Body Radiation;
- Bursts;
- Computational Astrophysics;
- Exosat Satellite;
- Hydrostatics;
- Time Response;
- Astrophysics