SALT spectroscopy of the flaring blazar J141922.55-083832.0
ATel #7167; D. A.H. Buckley, J. B. Breytenbach, A. Kniazev, M. M. Kotze, S. Potter (SAAO), E. Gorbovskoy, V. Lipunov (SAI)
on 2 Mar 2015; 23:35 UT
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Credential Certification: David Buckley (firstname.lastname@example.org)
Subjects: Optical, Quasar
A flare in the FSRQ blazar, J141922.55-083832.0, which was discovered by MASTER Kislovosk on 2015-02-21.9877 UT (ATel #7133) as an unfiltered 14.6 magnitude transient, was observed on 2015-03-01.00 UT at the SAAO using the 1.9 m telescope using the SHOC high speed EM-CCD camera. UBVR measurements confirmed the object was still in a bright flaring state (V < 15). Observations were then obtained with SALT RSS on 2015-03-01.01 UT using the PG900 lines/mm grating at an angle of 14.00 degrees.
An 1100s exposure spectrum, covering 3780 - 6850 Angstroms at a resolution of 4.8 Angstroms with a 1.25 arcsec slit, was obtained in clear conditions and seeing of 1.5 arcsec. The spectrum shows a single emission line at 5325 Angstroms, plus some very broad (~500 Angstroms) bumps at ~4200, 4600 and 6400 Angstroms, superimposed on a continuum steeply rising to the blue. If the emission line is interpreted to be the Mg II 2798 Angstroms line, then the implied redshift for this blazar is 0.903.