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INTEGRAL Observations of SS433: Analysis of Precessional and Orbital X-ray Periodicities

A. M. Cherepashchuk·R. A. Sunyaev·E. V. Seifina·E. A. Antokhina·D. I. Kosenko·S. V. Molkov·N. I. Shakura·K. A. Postnov·A. N. Timokhin·I. E. Panchenko
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Abstract

Hard X-ray INT observations of SS 433 carried out during 2003-2005 years with an analysis of precessional and orbital variability is presented. The width of X-ray eclipse in the 25-50 keV range at the precessional phase $ψ=0.1$ (accretion disk is open to observer) is higher than that in the Ginga 18.4-27.6 keV range. This fact suggests existance the presence of hot extended corona around the supercritical accretion disk. Spectrum of hard X-rays in the range 10-200 keV does not change with the precessional phase which also suggests that hard X-ray flux is generated in the hot extended corona around the accretion disk. The parameters of this hot corona are: kT=23-25 keV, τ= 1.8-2.8. Mass ratio estimated from the analysis of the ingress part of the eclipse light curve is in the range q=m_x/m_v=0.3-0.5.

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A. M. Cherepashchuk, R. A. Sunyaev, E. V. Seifina, E. A. Antokhina, D. I. Kosenko, S. V. Molkov, N. I. Shakura, K. A. Postnov, A. N. Timokhin, I. E. Panchenko. 2006-10-09. INTEGRAL Observations of SS433: Analysis of Precessional and Orbital X-ray Periodicities. https://arxiv.org/abs/astro-ph/0610235

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