ASASSN-16ar: Discovery of A Supernova in 2MASX J04283087-1739233
ATel #8565; G. Masi (Virtual Telescope Project, Ceccano, Italy), D. Bersier (LJMU), B. J. Shappee (Hubble Fellow, Carnegie Observatories), J. S. Brown, K. Z. Stanek, T. W.-S. Holoien, C. S. Kochanek, D. Godoy-Rivera, U. Basu (Ohio State), J. L. Prieto (Diego Portales; MAS), Subo Dong, Ping Chen (KIAA-PKU), J. Brimacombe (Coral Towers Observatory), G. Bock (Runaway Bay Observatory, Australia), S. Kiyota (Variable Star Observers League in Japan)
on 20 Jan 2016; 17:10 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Jonathan Brown (email@example.com)
Subjects: Optical, Supernovae, Transient
Referred to by ATel #: 8636
During the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN or "Assassin"), using data from the quadruple 14-cm "Cassius" telescope in Cerro Tololo, Chile, we discovered a new transient source, most likely a supernova, in the galaxy 2MASX J04283087-1739233.
ASASSN-16ar (AT 2016Z) was discovered in images obtained on UT 2016-01-17.21 at V~17.0 mag. We also detect the object in images obtained on UT 2016-01-14.18 (V~17.5) and UT 2016-01-18.05 (V~17.2). We do not detect (V>18.0) the object in images taken on UT 2016-01-12.22 and before. An image obtained on 2016-01-19 with the LCOGT 1-m robotic telescope at SAAO confirms the discovery of the transient. This figure shows the archival DSS image of the host (left) and the LCOGT confirmation image (right). The red circle has a radius of 5" and is centered on the position of the transient in the LCOGT image.
We obtained a spectrum of ASASSN-16ar on UT 2016-01-19 with the SPRAT spectrograph on the Liverpool Telescope. Classification performed with SNID (Blondin and Tonry 2007, ApJ, 666, 1024) suggests ASASSN-16ar to be a type Ia supernovae around 3 days after maximum light (best match: SN 2001N at 2.6 days) at the redshift of the host.
The position of ASASSN-16ar is approximately 0.1" North and 0.1" West from the center of the galaxy 2MASX J04283087-1739233 (z=0.031078, d=130 Mpc, via NED), giving an absolute V-band magnitude of approximately -18.7 (m-M=35.57, A_V=0.105). Properties of the new source and photometry are summarized in the tables below:
Object RA (J2000) DEC (J2000) Disc. UT Date Disc. V mag Approx. Abs. Mag Offset from Host (")
ASASSN-16ar 04:28:30.832 -17:39:23.37 2016-01-17.21 17.0 -18.7 0.14
Obs. UT Date V mag
Follow-up observations are encouraged.
We thank LCOGT and its staff for their continued support of ASAS-SN. ASAS-SN is supported by NSF grant AST-1515927, the Center for Cosmology and AstroParticle Physics (CCAPP) at OSU, the Mt. Cuba Astronomical Foundation, George Skestos, and the Robert Martin Ayers Sciences Fund. For more information about the ASAS-SN project, see the ASAS-SN Homepage and the list of all ASAS-SN transients.