ASAS-SN Discovery of A Probable Supernova in CGCG 080-055
ATel #7145; G. Krannich (Roof Observatory Kaufering), J. M. Fernandez (Observatory Inmaculada del Molino), J. Brimacombe (Coral Towers Observatory), 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), E. Falco (CfA), D. Szczygiel, G. Pojmanski (Warsaw University Observatory), S. Kiyota (Variable Star Observers League in Japan), W. Wiethoff (University of Minnesota, Duluth)
on 26 Feb 2015; 19:27 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Thomas Holoien (firstname.lastname@example.org)
Subjects: Optical, Supernovae, Transient
Referred to by ATel #: 7180
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, most likely a supernova, in the galaxy CGCG 080-055:
Object RA (J2000) DEC (J2000) Disc. UT Date Disc. V mag
ASASSN-15dz 16:41:20.87 +08:54:31.66 2015-02-20.59 17.0
ASASSN-15dz was discovered in images obtained on UT 2015-02-20.59 at V~17.0 mag. We also detect the object in images obtained on UT 2015-02-26.65 (V~16.6) and UT 2015-02-25.58 (V~16.6). We do not detect (V>17.3) the object in images taken on UT 2015-02-17.510 and before. Numerous images, including one obtained on UT 2015-02-26.44 with the LCOGT 1-m robotic telescope in Cerro Tololo, Chile, confirm the discovery of the transient. This figure shows the archival SDSS g-band image of the host (left) and the LCOGT confirmation image (right). The red circle has a radius of 2â and is centered on the position of the transient in the LCOGT image.
The position of ASASSN-15dz is approximately 0.9" South and 0.3" West from the center of the galaxy CGCG 080-055 (z=0.032216, d=136 Mpc, via NED), giving an absolute V-band magnitude of approximately -18.8 (m-M=35.67, A_V=0.17). 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.