[ Previous | Next | ADS ]

ASAS-SN Discovery of A Bright Transient in A Galaxy We Don't Know How Far, Far Away

ATel #6397; I. Cruz (Cruz Observatory), E. Conseil (Association Francaise des Observateurs d'Etoiles Variables), K. Z. Stanek, C. S. Kochanek, A. B. Davis, T. W.-S. Holoien, B. J. Shappee, U. Basu, J. F. Beacom (Ohio State), J. L. Prieto (Diego Portales; MAS), D. Bersier (LJMU), J. Brimacombe (Coral Towers Observatory), D. Szczygiel, G. Pojmanski (Warsaw University Observatory), S. Kiyota (Variable Star Observers League in Japan), J. Nicolas (Groupe SNAUDE, France)
on 16 Aug 2014; 16:03 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Krzysztof Stanek (stanek.32@osu.edu)

Subjects: Optical, Supernovae

During the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN or "Assassin"), using data from both the quadruple 14-cm "Brutus" telescope in Haleakala, Hawaii and the double 14-cm "Cassius" telescope in Cerro Tololo, Chile, we discovered a new transient source, most likely a supernova, near the galaxy GALEXASC J203406.21-015759.2:

Object       RA (J2000)     DEC (J2000)      Disc. UT Date   Disc. V mag  
ASASSN-14fo  20:34:06.432   -01:58:03.59     2014-08-15.49     15.8 
ASASSN-14fo was discovered in "Brutus" images obtained on UT 2014-08-15.49 at V=15.8. It is also present in "Cassius" images taken on UT 2014-08-14.29 at V=15.8 and in "Brutus" images taken on UT 2014-08-16.39, also at V=15.8. It might also be present, significantly fainter and subject to further analysis, in "Cassius" images obtained between UT 2014-08-01.17 and UT 2014-08-05.04.

Images obtained by I. Cruz on UT 2014-08-16.12 with a 43-cm telescope located near Reynoldsburg, Ohio, and nearly simultaneously by E. Conseil using a 0.35-m Slooh Space robotic telescope T2 at Mt. Teide, Canary Islands, confirm the discovery of the transient. This figure shows the archival DSS 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 derived from the I. Cruz confirmation image and reported above.

The position of ASASSN-14fo is approximately 6" from the center of GALEXASC J203406.21-015759.2, which, while clearly a galaxy in DSS images, has no redshift available in NED. We note that ASASSN-14fo is currently, in V-band, at least 1 magnitude brighter than its likely host galaxy. Follow-up observations, especially spectroscopy, 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.