Study of orbital and superorbital variability of LSI+61 degrees 303 with X-ray data

: Chernyakova M, Babyk I, Malyshev D, Vovk I, Tsygankov S, Takahashi H, Fukazawa Y

Publisher: OXFORD UNIV PRESS

: Oxford

: 2017

: Monthly Notices of the Royal Astronomical Society

: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY

: MON NOT R ASTRON SOC

: 470

: 2

: 1718

: 1728

: 11

: 0035-8711

: 1365-2966

DOI: https://doi.org/10.1093/mnras/stx1335

LSI + 61 degrees 303 is one of the few X-ray binaries with a Be star companion from which radio, X-rays and high-energy gamma-ray (GeV and TeV) emission have been observed. The nature of the high-energy activity of the system is not yet fully understood, but it is widely believed that it is generated due to the interaction of the relativistic electrons leaving the compact object with the photons and non-relativistic wind of the Be star. The superorbital variability of the system has been observed in the radio, optical and X-ray domains and could be due to the cyclic change of the Be star disc size. In this paper, we systematically review all publicly available data from Suzaku, XMM-Newton, Chandra and Swift observatories in order to measure the absorption profile of the circumstellar Be disc as a function of orbital and superorbital phases. We also discuss short-term variability of the system, found during the analysis and its implications for the understanding of the physical processes in this system.