Geometry of accretion in Soft X-ray Transients
Abstract
We present results of modelling Ginga data of a number of Soft X-ray Transient sources performed with the aim of constraining the geometry of accretion during various stages of the sources' evolution. Assuming a generic geometry of a central, extended X-ray source with an external, optically thick accretion disk, we use consistent models of X-ray reprocessing to constrain the inner radius of the accretion disk and its ionization state. We show that the evolution of GS 1124-68 (Nova Muscae 1991) and GS 2000+25 agree qualitatively with the recent ideas linking the high/low state transition with changing radius of the optically thick disk, but the case of GS 2023+33 (V404 Cyg) poses a problem for any model.
- Publication:
-
Accretion processes in Astrophysical Systems: Some like it hot! - eigth AstroPhysics Conference
- Pub Date:
- April 1998
- DOI:
- 10.1063/1.55912
- arXiv:
- arXiv:astro-ph/9712190
- Bibcode:
- 1998AIPC..431..319Z
- Keywords:
-
- 98.70.Qy;
- 97.10.Gz;
- 97.80.-d;
- X-ray sources;
- X-ray bursts;
- Accretion and accretion disks;
- Binary and multiple stars;
- Astrophysics
- E-Print:
- Aipproc LaTeX (4 pages, 4 figures), to appear in Proc. of the 8th October Astrophysics Conference in Maryland, "Accretion Processes in Astrophysical Systems", S. S. Holt &