ASAS-SN Discovery of A Probable Supernova in VV 790a
ATel #8480; G. Masi (Virtual Telescope Project, Ceccano, Italy), I. Cruz (Cruz Observatory), J. Brimacombe (Coral Towers Observatory), 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), S. Kiyota (Variable Star Observers League in Japan), L. A.G. Monard (Klein Karoo Observatory)
on 31 Dec 2015; 04:02 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Jonathan Brown (brown@astronomy.ohio-state.edu)
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 VV 790a.
ASASSN-15uu was discovered in images obtained on UT 2015-12-29.34 at V~16.7 mag. We also detect the object in images obtained on UT 2015-12-30.28 (V~16.5). We do not detect (V>16.8) the object in images taken on UT 2015-12-27.36 and before. Multiple images obtained on 2015-12-30 confirm the discovery of the transient. This figure shows the archival SDSS g-band image of the host (left) and the I. Cruz confirmation image (right). The red circle has a radius of 5" and is centered on the position of the transient in the I. Cruz image.
The position of ASASSN-15uu is approximately 1.6" North and 0.2" East from the center of the galaxy VV 790a (z=0.026795, d=108 Mpc, via NED), giving an absolute V-band magnitude of approximately -18.6 (m-M=35.12, A_V=0.188). 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-15uu 01:43:56.574 +17:03:44.44 2015-12-29.34 16.7 -18.6 1.61
Obs. UT Date V mag
2015-12-27.36 >16.8
2015-12-29.34 16.7
2015-12-30.28 16.5
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.
