ASAS-SN Discovery of A Possible Extreme Luminosity Transient in SDSS J130408.52+521846.4
ATel #6853; S. Kiyota (Variable Star Observers League in Japan), T. W.-S. Holoien, K. Z. Stanek, C. S. Kochanek, A. B. Davis, G. Simonian, U. Basu, N. Goss, J. F. Beacom (Ohio State), B. J. Shappee (Hubble Fellow, Carnegie Observatories), J. L. Prieto (Diego Portales; MAS), D. Bersier (LJMU), Subo Dong (KIAA-PKU), P. R. Wozniak (LANL), J. Brimacombe (Coral Towers Observatory), D. Szczygiel, G. Pojmanski (Warsaw University Observatory), E. Conseil (Association Francaise des Observateurs d'Etoiles Variables), R. A. Koff (Antelope Hills Observatory), B. Nicholls (Mt. Vernon Obs., New Zealand), J. Nicolas (Groupe SNAUDE, France)
on 28 Dec 2014; 19:01 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Thomas Holoien (tholoien@astronomy.ohio-state.edu)
Subjects: Optical, Supernovae, Transient
During the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN or "Assassin"), using data from the quadruple 14-cm "Brutus" telescope in Haleakala, Hawaii, we discovered a new transient source, possibly a luminous supernova, in the galaxy SDSS J130408.52+521846.4:
Object RA (J2000) DEC (J2000) Disc. UT Date Disc. V mag
ASASSN-14ms 13:04:08.69 +52:18:46.5 2014-12-26.61 16.5
ASASSN-14ms was discovered in images obtained on UT 2014-12-26.61 at V~16.5 mag. We also detect the object in images obtained on UT 2014-12-27.58 (V~16.6). We do not detect (V>17.1) the object in images taken on UT 2014-12-15.510 and before. An image obtained by S. Kiyota on UT 2014-12-28.51 using a Planewave CDK 0.61-m telescope located at Sierra Remote Observatory confirms the discovery of the transient. This figure shows the archival SDSS g-band image of the host (left) and the S. Kiyota confirmation image (right). The red circle has a radius of 3â and is centered on the position of the transient in the S. Kiyota image.
The position of ASASSN-14ms is approximately 1.1" South and 0.8" East from the center of SDSS J130408.52+521846.4, an extended source in SDSS images with no available spectroscopic redshift in NED (see the SDSS page here). The potential host has a PhotoZ of 0.169675 +/- 0.09043, and if we take this PhotoZ to be accurate, the transient would have an absolute magnitude of approximately -23.1 (m-M=39.58, A_V=0.031). Follow-up observations, particularly spectroscopy, are encouraged.
We thank LCOGT and its staff for their continued support of ASAS-SN. For more information about the ASAS-SN project, see the ASAS-SN Homepage and the list of all ASAS-SN transients.
