Detection of an unprecedented outburst in IDV QSO TXS0917+624
ATel #11048; O. I. Spiridonova, A. S. Moskvitin, V. V. Vlasyuk (Special Astrophysical Observatory of the Rus. Ac. Sci.)
on 10 Dec 2017; 09:35 UT
Credential Certification: Alexander Moskvitin (firstname.lastname@example.org)
Subjects: Optical, Quasar
Referred to by ATel #: 11187
We report on an unprecedented optical flare of TXS0917+624 --- popular QSO (z=1.446) with effects of intraday variability in radio range. Our measurements, made with 1-meter telescope of SAO of RAS, equipped by UBVRI CCD photometer, showed that apparent magnitude of object in R-band increased up to 15.34 +/- 0.02 on December 8th, 2017 (MJD = 58096.5) and 15.31 +/- 0.03 on December 9th, 2017 (MJD = 58097.5). That is 2 mag brighter than the flux value, measured by us on November 18th: 17.44 +/- 0.02. It is very intriguing, if take into account it's low global flux variations within last 15 years. Brightness of TXS0917+624 in February 2016 -- November 2017 was between R=17.3 and R=18.1. Our earlier data on complete range of flux variation in 2001--2015 were between R=18.1 and 19.5. We encourage further multi wavelength studies of this object.