Geometry of accretion in Soft X-ray Transients

P. T. Zycki; C. Done; D. A. Smith

doi:10.1063/1.55912

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arXiv · astro-ph/9712190

Geometry of accretion in Soft X-ray Transients

P. T. Zycki·C. Done·D. A. Smith

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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 the inner radius of the optically thick disk, but the case of GS 2023+33 (V404 Cyg) poses a problem for any model.

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P. T. Zycki, C. Done, D. A. Smith. 1997-12-15. Geometry of accretion in Soft X-ray Transients. https://doi.org/10.1063/1.55912

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