NOT spectroscopic classification of Gaia16aax as a likely AGN outburst
ATel #8669; S. Mattila, J. Harmanen (Turku), T. Reynolds (Turku, NOT), M. Fraser, S. Hodgkin (IoA), N. Blagorodnova (Caltech), L. Wyrzykowski (Warsaw Observatory, Poland), E. Kankare (QUB)
on 10 Feb 2016; 21:51 UT
Credential Certification: Seppo Mattila (seppo.mattila@utu.fi)
We report the spectroscopic classification of Gaia16aax based on a low-resolution spectrum obtained on 2016 Feb. 10.3 UT, with the Nordic Optical Telescope (+ ALFOSC; range 320-910 nm). Gaia16aax was discovered by the Gaia Photometric Science Alerts programme at magnitude of 18.33 on 2016 Jan. 26.7 UT and shows a very slowly rising smooth light curve. The position of the transient as reported by Gaia is ~0.1" from the catalogued position of the galaxy SDSS J143418.47+491236.5 which is classified as a QSO BROADLINE in the Sloan Digital Sky Survey at a redshift of z = 0.2485. The new spectrum showing similarity to the archival spectrum from the Sloan Digital Sky Survey covers also a strong Mg II (2800A) line and shows a rising continuum blueward of 4000A. A cross-correlation with a library of spectra using the "SNID" code (Blondin & Tonry 2007, ApJ, 666, 1024) gives a good match to an AGN.
We acknowledge ESA Gaia, DPAC and the Photometric Science Alerts Team (http://gsaweb.ast.cam.ac.uk/alerts).
