ASAS-SN Discovery of A Probable Supernova in SDSS J140149.76+342139.7
ATel #6342; I. Cruz (Cruz Observatory), S. Kiyota (Variable Star Observers League in Japan), E. Conseil (Association Francaise des Observateurs d'Etoiles Variables), J. Brimacombe (Coral Towers Observatory), T. W.-S. Holoien, 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 25 Jul 2014; 20:11 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Krzysztof Stanek (stanek.32@osu.edu)
Subjects: Optical, Supernovae, Transient
Referred to by ATel #: 6346
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 SDSS J140149.76+342139.7:
Object RA (J2000) DEC (J2000) Disc. UT Date Disc. V mag
ASASSN-14em 14:01:49.99 +34:21:42.7 2014-07-24.27 17.3
ASASSN-14em was discovered in images obtained on UT 2014-07-24.27 at V~17.3 mag. We also detect the object in images obtained on UT 2014-07-25.26 (V~17.4) but we do not detect (V>17.6) the object in images taken on UT 2014-07-23.33 and before. Images obtained by I. Cruz on UT 2014-07-25.13 with a Planewave CDK-17 43-cm telescope (+Apogee CG16M camera) located near Reynoldsburg, Ohio; by E. Conseil on UT 2014-07-24.99 using a 0.35m f/11 Schmidt-Cassegrain + STL-11000M from Slooh Space robotic telescope C1 in La Dehesa, Chile; by S. Kiyota on UT 2014-07-25.16 using a Planewave CDK 0.43-m telescope located near Mayhill, New Mexico; and by J. Brimacombe on UT 2014-07-25.16 with the RCOS 51-cm telescope in New Mexico confirm the discovery of the transient. This
figure shows the archival SDSS g-band image of the host (left) and the Cruz Observatory confirmation image (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-14em is approximately 13.8" North and 2.9" West from the center of the galaxy SDSS J140149.76+342139.7 (z=0.035124, d=151 Mpc, via NED), giving an absolute V-band magnitude of approx. -18.6 (m-M=35.90, A_V=0.04). 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.