Optical brightening of CSS120103:002748-055559: spectroscopic confirmation as a blazar
ATel #4606; E. Breedt, B. T. Gaensicke (University of Warwick), S. G. Parsons (Universidad de Valparaiso)
on 26 Nov 2012; 11:42 UT
Credential Certification: Elme Breedt (E.Breedt@warwick.ac.uk)
Subjects: Optical, AGN, Blazar
Referred to by ATel #: 4612
The Catalina Real time Transient Survey (CRTS) identified the variable blue source at RA 00h27m48.41s, Dec -05d59m59.14s as an optical transient on 2012 January 3, after a rapid 1.5 magnitude brightening above its average quiescent magnitude of 18.6(2) (unfiltered). The following observation of the same field (2012 August 13.56 UTC) found the source at a magnitude of 15.95(4), a 2.89 magnitude brightness increase in 295 days. The latest CRTS measurement available is 16.47(3) mag on 2012 August 28.52 UTC.
We obtained a single-epoch optical spectrum of this source, CSS120103:002748-055559, using the ISIS spectrograph on the 4.2-m William Herschel Telescope in La Palma, Canary Islands, on 2012 October 20.88. The spectrum displays broad emission lines of Hydrogen and MgII, and clearly identifies the source as a redshift z=0.42816(3) blazar.
An earlier GALEX detection of the source was flagged as a possible QSO by Atlee & Gould 2007 ApJ 664 53. The NVSS also includes a weak detection at this position.
The 6 year historical Catalina Sky Survey (CSS) lightcurve shows only small amplitude variability prior to the current flare. Both the SDSS DR9 and USNO-A2.0 photometry are consistent with the quiescent magnitude.
Spectrum available at this url (pdf)
