ASAS-SN Discovery of A Probable Supernova in ESO 381-IG048
ATel #6936; S. Kiyota (Variable Star Observers League in Japan), T. W.-S. Holoien, K. Z. Stanek, C. S. Kochanek, A. B. Danilet, 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)
on 16 Jan 2015; 18:16 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Thomas Holoien (email@example.com)
Subjects: Optical, Supernovae, Transient
Referred to by ATel #: 6948
During the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN or "Assassin"), using data from the double 14-cm "Cassius" telescope in Cerro Tololo, Chile, we discovered a new transient source, most likely a supernova, in the galaxy ESO 381-IG048:
Object RA (J2000) DEC (J2000) Disc. UT Date Disc. V mag
ASASSN-15bb 13:01:06.38 -36:36:00.17 2015-01-16.27 16.8
ASASSN-15bb was discovered in images obtained on UT 2015-01-16.27 at V~16.8 mag. We do not detect (V>17.0) the object in images taken on UT 2015-01-14.32 and before. An image obtained by S. Kiyota on UT 2015-01-16.65 using a 0.5m CDK + FLI PL-9000 at the ITelescope.NET site at Siding Springs Observatory confirms the discovery of the transient. This figure shows the archival DSS image of the host (left) and the S. Kiyota confirmation image (right). The red circle has a radius of 3.0" and is centered on the position of the transient in the S. Kiyota image.
The position of ASASSN-15bb is approximately 2.2" North and 10.0" East from the center of the galaxy ESO 381-IG048 (z=0.01587, d=70.3 Mpc, via NED), giving an absolute V-band magnitude of approximately -17.6 (m-M=34.23, A_V=0.13). Follow-up observations are encouraged.
We thank LCOGT and its staff for their continued support of ASAS-SN. ASAS-SN is supported in part by Mt. Cuba Astronomical Foundation. For more information about the ASAS-SN project, see the ASAS-SN Homepage and the list of all ASAS-SN transients.