Optical brightening of the XRB SAX J2103.5+4545
ATel #13938; T. S. Grishina, E. N. Kopatskaya, V. M. Larionov (St. Petersburg University)
on 12 Aug 2020; 13:13 UT
Credential Certification: V. Larionov (vlar@astro.spbu.ru)
Subjects: Optical, Binary, Neutron Star, Variables
We report on the renewed optical activity of the high-mass X-ray binary system SAX J2103.5+4545. The source is monitored with 0.7-m AZT-8 (CrAO, Russia) telescope. In the night of 2020-07-11 (MJD 59042.4) the brightness of the optical counterpart was R= 13.16+/-0.02 and in the night of 2020-08-10 (MJD 59072.3) its brightness reached R= 13.05+/-0.02, as compared to quiescent level of R= 13.62+/-0.02 in the night 2020-06-06 (MJD 59007.5). Optical light curve of SAX J2103.5+4545 is presented here. The previous optical high state that culminated in the end of April of 2019 was followed by the onset of X-ray activity of the source, see Swift/BAT light curve. Multiwavelength observations of the system are desirable for monitoring of its activity.
