ASAS-SN Discovery of A Probable Supernova in ESO 416-G039
ATel #6372; T. W.-S. Holoien (Ohio State), J. Brimacombe (Coral Towers Observatory), K. Z. Stanek, B. J. Shappee, A. B. Davis, C. S. Kochanek, J. Jencson, U. Basu, J. F. Beacom (Ohio State), J. L. Prieto (Diego Portales), D. Bersier (LJMU), D. Szczygiel, G. Pojmanski (Warsaw University Observatory)
on 5 Aug 2014; 17:54 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 #: 6384
During the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN or "Assassin"), using data from the recently commissioned double 14-cm "Cassius" telescope in Cerro Tololo, Chile, we discovered a new transient source, most likely a supernova, in the galaxy ESO 416-G039:
Object RA (J2000) DEC (J2000) Disc. UT Date Disc. V mag
ASASSN-14fa 02:52:23.06 -31:49:18.0 2014-08-05.31 16.1
ASASSN-14fa was discovered in images obtained on UT 2014-08-05.31 at V~16.1 mag. The object is visible in images obtained with multiple ASAS-SN cameras, on UT 2014-08-03.34 (V~16.3) and UT 2014-08-02.30 (V~16.3). We do not detect (V>17.6) the object in images taken on UT 2014-08-01.35 and before. Followup images obtained by J. Brimacombe on UT 2014-08-05.70 with the RCOS 41-cm telescope near Siding Spring Observatory and on UT 2014-08-05.70 with the LCOGT 1-m telescope at Siding Springs Observatory confirm the detection of the transient. This figure shows the ASAS-SN V-band reference image (top left), the ASAS-SN 2014-08-05.31 V-band discovery image (top right), the archival DSS image of the host galaxy (bottom left) and the LCOGT 2014-08-05.70 g-band confirmation image (bottom right). The red circle has a radius of 5" and is centered on the ASAS-SN position of the transient.
The ASAS-SN position of ASASSN-14fa is approximately 16" South and 9.7" East from the center of the galaxy ESO 416-G039 (z=0.022589, d=92.2 Mpc, via NED), giving an absolute V-band magnitude of approximately -18.8 (m-M=34.82, A_V=0.056). Follow-up observations are encouraged.
We thank LCOGT and its staff for their continued support of ASAS-SN. For more information about the ASAS-SN project, see the ASAS-SN Homepage and the list of all ASAS-SN transients.
