Observations of X-ray Binaries at the Caucasus Mountain Observatory of SAI MSU

Abstract

This review presents the results of observations of high-mass and low-mass X-ray binaries carried out at the Caucasus Mountain Observatory of SAI MSU over the past five years. Interpretation of these observations within the framework of complex unconventional models has led to a number of interesting results. In particular, on the basis of the secular evolutionary increase in the orbital period of the microquasar SS 433 that we discovered, we managed to prove that the relativistic object here is a black hole, and the SS 433 system itself evolves as a semi-detached system due to the fact that the distance between its components increases with time, which prevents the formation of a common envelope. In the microquasar Cyg X-3, an anomalous behavior of IR color indices with the phase of the orbital period was detected. Modeling is carried out and estimates of the parameters of this system are given. In low-mass X-ray binaries (X-ray novae), black hole masses are estimated, spectra of advection-dominated disks are constructed, and an observational justification is given for modern results of three-dimensional gas-dynamic calculations for interacting binaries.