ASAS-SN Discovery of A Possible Supernova near GALEXASC J202523.12-532407.2
ATel #8214; Subo Dong (KIAA-PKU), K. Z. Stanek, J. S. Brown, 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), Ping Chen (KIAA-PKU), J. Brimacombe (Coral Towers Observatory)
on 25 Oct 2015; 14:01 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Subo Dong (email@example.com)
Subjects: Optical, Cataclysmic Variable, Supernovae, Transient
Referred to by ATel #: 8978
ASASSN-15rx was discovered in images obtained on UT 2015-10-24.06 at V~16.6 mag. We also detect the object in images obtained on UT 2015-10-23.15 (V~16.4). We do not detect (V>16.9) the object in images taken on UT 2015-10-21.07 and before. A V-band image obtained on 2015-10-24 with the LCOGT 1-m robotic telescope at Sutherland confirms the discovery of the transient. This figure shows the archival DSS image of the host (left) and the LCOGT V-band confirmation image (right). The red circle has a radius of 5" and is centered on the position of the transient in the LCOGT image.
The position of ASASSN-15rx is approximately 0.4" away from the center of the UV source GALEXASC J202523.12-532407.2 (no redshift information available from NED). ASASSN-15rx is a possible supernova candidate but there is also a possibility that it is a CV. Properties of the new source and photometry are summarized below:
Object RA (J2000) DEC (J2000) Disc. UT Date Disc. V mag Approx. Abs. Mag Offset from Host (")
ASASSN-15rx 20:25:23.13 -53:24:07.7 2015-10-24.06 16.6 N/A 0.4
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.