ASASSN-16mw: Discovery of A Probable Supernova Near GALEXASC J044521.39+751011.6
ATel #9718; T. W.-S. Holoien, K. Z. Stanek, C. S. Kochanek, J. S. Brown, J. Shields (Ohio State), B. J. Shappee (Hubble Fellow, Carnegie Observatories), J. L. Prieto (Diego Portales; MAS), D. Bersier (LJMU), Subo Dong, S. Bose, Ping Chen (KIAA-PKU), J. Brimacombe (Coral Towers Observatory)
on 6 Nov 2016; 02:07 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Thomas Holoien (tholoien@astronomy.ohio-state.edu)
Subjects: Optical, Supernovae, Transient
p>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, near the UV source GALEXASC J044521.39+751011.6.
ASASSN-16mw (AT 2016hvp) was discovered in images obtained on UT 2016-11-05.57 at V~15.8 mag. We also detect the object in images obtained on UT 2016-11-01.46 (V~17.2). We do not detect (V>17.7) the object in images taken on UT 2016-10-27.48 and before. This figure shows the archival DSS image of the host (left), the ASAS-SN V-band reference image of the host (center), and the ASAS-SN V-band discovery image (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-16mw is approximately 20.9" South and 22.2" West from the center of the UV source GALEXASC J044521.39+751011.6, which is uncatalogued but appears to be a spiral galaxy. GALEXASC J044521.39+751011.6 has no redshift available in NED, but does have a high extinction (A_V=0.489). 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-16mw 04:45:15.60 +75:09:50.8 2016-11-05.57 15.8 N/A 30.49
Obs. UT Date V mag
2016-10-27.48 >17.7
2016-11-01.46 17.2
2016-11-05.57 15.8
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, and the 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.
