ASASSN-16el: Discovery of A Probable Supernova in UGC 04671
ATel #8947; J. S. Brown, K. Z. Stanek, T. W.-S. Holoien, C. S. Kochanek, D. Godoy-Rivera, U. Basu (Ohio State), B. J. Shappee (Hubble Fellow, Carnegie Observatories), J. L. Prieto (Diego Portales; MAS), D. Bersier (LJMU), Subo Dong, Ping Chen (KIAA-PKU), J. Brimacombe (Coral Towers Observatory)
on 13 Apr 2016; 22:10 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Jonathan Brown (email@example.com)
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, most likely a supernova, in the galaxy UGC 04671.
ASASSN-16el (AT 2016bmf) was discovered in images obtained on UT 2016-04-13.26 at V~16.4 mag. We do not detect (V>17.3) the object in images taken on UT 2016-04-09.35 and before. This figure shows the ASAS-SN V-band reference image (left), the ASAS-SN discovery image (middle), and the archival DSS image of the host (right). The red circle has a radius of 10" and is centered on the position of the transient in the discovery image.
The position of ASASSN-16el is approximately 9.3" South and 33.8" West from the center of the galaxy UGC 04671 (z=0.013519, d=58.2 Mpc, via NED), giving an absolute V-band magnitude of approximately -17.5 (m-M=33.83, A_V=0.053). We note that this may be the same object as AT 2016bme reported via TNS by The Greek Supernovae Survey Team near the same galaxy, but most likely reported with erroneous coordinates. 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-16el 08:56:39.08 +52:06:10.01 2016-04-13.26 16.4 -17.5 35.1
Obs. UT Date V mag
Follow-up observations are encouraged.
While we are participating in the TNS system to minimize potential confusion, ASAS-SN will continue using ASASSN-16xx transient names as our primary nomenclature (including supernovae, but also other classes of transients), and we encourage others to do the same. We prefer merging the names as ASASSN-16xx (AT2016xyz) to preserve, rather than anonymize, the origin of the transient.
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.