ASAS-SN Discovery of A Bright Transient Near 2MASX J01553890+4859477
ATel #8260; T. W.-S. Holoien, K. Z. Stanek, C. S. Kochanek, J. S. Brown, 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), S. Kiyota (Variable Star Observers League in Japan), G. Masi (Virtual Telescope Project, Ceccano, Italy), L. A.G. Monard (Klein Karoo Observatory), B. Nicholls (Mt. Vernon Obs., New Zealand)
on 9 Nov 2015; 02:58 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Thomas Holoien (tholoien@astronomy.ohio-state.edu)
Subjects: Optical, Supernovae, Transient
Referred to by ATel #: 8270
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, possibly a supernova, near the galaxy 2MASX J01553890+4859477.
ASASSN-15sr was discovered in images obtained on UT 2015-11-08.40 at V~15.6 mag. We do not detect (V>17.9) the object in images taken on UT 2015-11-04.37 and before. This figure shows the archival DSS image of the host (left), the ASAS-SN V-band reference image of the field (center), and the ASAS-SN V-band discovery image (right). The red circle has a radius of 5" and is centered on the position of the transient in the ASAS-SN image.
The position of ASASSN-15sr is approximately 7.3" North and 9.4" East from the center of the galaxy 2MASX J01553890+4859477, which has no redshift available in NED. There is also a possible stellar source near the position of the transient. Given the proximity of this source, the transient could be a supernova or a cataclysmic variable star. 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-15sr 01:55:39.91 +48:59:55.26 2015-11-08.40 15.6 N/A 11.9
Obs. UT Date V mag
2015-11-04.37 >17.9
2015-11-08.40 15.6
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 Mt. Cuba Astronomical Foundation, the Center for Cosmology and AstroParticle Physics (CCAPP) at OSU, 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.