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arXiv · 0805.1001

Modeling of non-stationary accretion disks in X-ray novae A 0620-00 and GRS 1124-68 during outburst

V. F. Suleimanov·G. V. Lipunova·N. I. Shakura
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Abstract

We address the task of modeling soft X-ray and optical light curves of X-ray novae in the high/soft state. The analytic model of viscous evolution of an externally truncated accretion α-disk is used. Relativistic effects near a Kerr black hole and self-irradiation of an accretion disk are taken into account. The model is applied to the outbursts of X-ray nova Monocerotis 1975 (A 0620-00) and X-ray nova Muscae 1991 (GRS 1124-68). Comparison of observational data with the model yields constraints on the angular momentum (the Kerr parameter) of the black holes in A 0620-00 and GRS 1124-68: 0.3-0.6 and \leq 0.4, and on the viscosity parameter αof the disks: 0.7-0.95 and 0.55-0.75. We also conclude that the accretion disks should have an effective geometrical thickness 1.5-2 times greater than the theoretical value of the distance between the photometric layers.

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V. F. Suleimanov, G. V. Lipunova, N. I. Shakura. 2008-09-24. Modeling of non-stationary accretion disks in X-ray novae A 0620-00 and GRS 1124-68 during outburst. https://doi.org/10.1051/0004-6361%3A200810155

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