ASAS-SN Discovery of A Bright Probable Supernova in a Galaxy with Unknown Redshift
ATel #7447; Subo Dong (KIAA-PKU), K. Z. Stanek, T. W.-S. Holoien, C. S. Kochanek, A. B. Danilet, G. Simonian, U. Basu, N. Goss, J. F. Beacom, T. A. Thompson (Ohio State), B. J. Shappee (Hubble Fellow, Carnegie Observatories), J. L. Prieto (Diego Portales; MAS), D. Bersier (LJMU), P. R. Wozniak (LANL), E. Falco (CfA), J. Brimacombe (Coral Towers Observatory), D. Szczygiel, G. Pojmanski (Warsaw University Observatory)
on 26 Apr 2015; 14:28 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Subo Dong (firstname.lastname@example.org)
Subjects: Optical, Supernova Remnant
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, bright transient source, most likely a supernova, in the galaxy GALEXASC J134316.80-313318.2:
Object RA (J2000) DEC (J2000) Disc. UT Date Disc. V mag
ASASSN-15hx 13:43:16.692 -31:33:21.55 2015-04-26.18 15.0
ASASSN-15hx was discovered in images obtained on UT 2015-04-26.18 at V~15.0. and it was also detected on UT 2015-04-23.19 at V~16.7. We do not detect (V>17.7) this object in images taken on UT 2015-04-17.07 and before.
See the ASAS-SN discovery image. The top left panel shows the reference image, the top right shows the DSS image on the same angular scale, the lower left is one of the 90-sec V-band images on 04/26 and the lower right is the image subtraction residual image on 04/26. The circle with the 15" radius has the same position.
The position of ASASSN-15hx is approximately 4" from the center of the galaxy GALEXASC J134316.80-313318.2 (no redshift information available from NED). 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.