ASASSN-17ad: Discovery of A Probable Supernova in CGCG 314-011
ATel #9944; R. S. Post (Post Astronomy), J. Shields (OSU), Subo Dong (KIAA-PKU), K. Z. Stanek, C. S. Kochanek, T. W.-S. Holoien, J. S. Brown, T. A. Thompson (Ohio State), B. J. Shappee (Hubble Fellow, Carnegie Observatories), J. L. Prieto (Diego Portales; MAS), D. Bersier (LJMU), S. Bose, Ping Chen (KIAA-PKU), J. Brimacombe (Coral Towers Observatory), S. Kiyota (Variable Star Observers League in Japan), J. M. Fernandez (Observatory Inmaculada del Molino), G. Masi (Virtual Telescope Project, Ceccano, Italy), P. Marples (Leyburn Observatory, Australia), G. Bock (Runaway Bay Observatory, Australia)
on 5 Jan 2017; 21:15 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Krzysztof Stanek (firstname.lastname@example.org)
Subjects: Optical, Supernovae
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 CGCG 314-011.
ASASSN-17ad (AT 2017ah) was discovered in images obtained on UT
2017-01-04.55 at V~17.3 mag. We do not detect (V>17.6) the object in
images taken on UT 2017-01-03.59 and before. An image obtained on
2017-01-04 by R. Post confirms the discovery of the transient. This figure
shows the archival SDSS image of the host (left) and the R. Post
confirmation image (right). The red circle has a radius of 5" and is
centered on the position of the transient in the R. Post image.
The position of ASASSN-17ad is approximately 3.16" North and 2.138"
West from the center of the galaxy CGCG 314-011 (z=0.032863, d=140
Mpc, via NED), giving an absolute V-band magnitude of approximately
-18.5 (m-M=35.73, A_V=0.032). 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-17ad 11:10:01.955 63:38:34.16 2017-01-04.55 17.3 -18.5 3.82
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-17xx 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-17xx (AT 2017xyz) to preserve, rather than
anonymize, the origin of the transient.
We thank Las Cumbres Observatory 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
Chinese Academy of Sciences South America Center for Astronomy
(CASSACA), 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