Optical activity of the X-ray source 1RXS J051439.2-021615
ATel #11250; K. Gazeas (National and Kapodistrian University of Athens)
on 2 Feb 2018; 17:22 UT
Credential Certification: Kosmas Gazeas (kgaze@phys.uoa.gr)
Subjects: Optical, Transient, Variables
The X-ray source 1RXS J051439.2-021615 (RA 05h14m39.20s, Dec -02d16m15.00, J2000.0) showed an optical V-band flare, during the night of 25/26 January 2018 (JD=2458114). While the source had a relatively stable luminosity of V=12.84(1) mag during the past days, there was a sudden increase of the observed flux, which started at HJD=2458144.43313 and reached the peak of V=11.85(1) mag at HJD= 2458144.43741 within a few minutes. TYC 4755-59-1 was used as a comparison for the photometric reduction and it was found to be a good standard with V=12.11(1) mag. The observations were obtained in a 3-min cadence and the brightness was increased by 1 mag within 9 minutes with a slope of ~0.11 mag/minute. An exponential decline was observed until the end of the night, when the magnitude dropped from V=11.85(1) mag to V=12.72(1) mag in approximately 45 minutes. Multi-wavelength observations on this X-ray source are highly encouraged, while the robotic and remotely controlled telescope at the University of Athens Observatory (UOAO) will continue to follow the target in BVRI optical bands in the following days. Questions regarding the current flare and data availability should be directed to Dr. Kosmas Gazeas (kgaze@phys.uoa.gr). A light curve sample can be found under the link: http://observatory.phys.uoa.gr/menu_news_events_en.html