Diagnostics of SS433 with the RXTE

¹ Max-Planck-Institute für Astrophysik, Karl-Schwarzschild-Str. 1, 85740 Garching bei München, Germany
² Space Research Institute, Russian Academy of Sciences, Profsoyuznaya 84/32, 117997 Moscow, Russia e-mail: kate@hea.iki.rssi.ru
³ Special Astrophysical Observatory, Nizhnij Arkhyz, Karachaevo-Cherkesiya 369167, Russia
⁴ Sternberg Astronomical Institute, 119992 Moscow, Russia

Received: 28 December 2005
Accepted: 24 August 2006

Abstract

We present our analysis of the extensive monitoring of SS433 by the RXTE observatory collected over the period 1996–2005. The difference between energy spectra taken at different precessional and orbital phases shows the presence of strong photoabsorption ( cm^-2) near the optical star, probably due to its powerful, dense wind. Therefore the size of the secondary deduced from analysis of X-ray orbital eclipses might be significantly larger than its Roche lobe size, which must be taken into account when evaluating the mass ratio from analysis of X-ray eclipses. Assuming that a precessing accretion disk is geometrically thick, we recover the temperature profile in the X-ray emitting jet that best fits the observed precessional variations in the X-ray emission temperature. The hottest visible part of the X-ray jet is located at a distance of , or ~ cm from the central compact object, and has a temperature of about  keV. We discovered appreciable orbital X-ray eclipses at the “crossover” precessional phases (jets are in the plane of the sky, disk is edge-on), which under model assumptions put a lower limit on the size of the optical component and an upper limit on a mass ratio of binary companions , if the X-ray opaque size of the star is not larger than .