ASAS-SN Discovery of a Likely Supernova in NGC 2765
ATel #5415; J. Brimacombe (Coral Towers Observatory), J. L. Prieto (Princeton), K. Z. Stanek, B. J. Shappee, C. S. Kochanek, T. W-S. Holoien, J. Jencson, U. Basu, J. F. Beacom (Ohio State), D. Szczygiel, G. Pojmanski (Warsaw University Observatory), M. Dubberley, M. Elphick, S. Foale, E. Hawkins, D. Mullins, W. Rosing, R. Ross, Z. Walker (Las Cumbres Observatory)
on 24 Sep 2013; 22:28 UT
Credential Certification: Jose L. Prieto (firstname.lastname@example.org)
Subjects: Optical, Supernovae, Transient
During the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN or "Assassin"), using data from the double 14-cm "Brutus" telescope in Haleakala, Hawaii, we discovered a new optical transient source, likely a supernova:
Object RA(J2000) Dec(J2000) Disc. UT Date Disc. V Mag
ASASSN-13dd 09:07:36.75 +03:23:39.7 2013 Sep. 24.63 15.21
ASASSN-13dd was discovered in images obtained on UT Sep. 24.63, undetected
in our previous images of the field obtained on 2013 May 2. Confirmation
images (6x300 sec) were obtained on UT Sep. 24.78 by J. Brimacombe
from the Coral Towers Observatory (Cairns, Australia) using a 16" RCOS
telescope with an IR filter (close to I-band). This
shows the ASAS-SN reference image (top left), ASAS-SN discovery subtraction image
(top right), CTO confirmation image (bottom left), and archival SDSS r-band
image (bottom right). The red circle has a radius of 7.5" at the position
of the SN candidate in each image.
The transient is approximately 5.2" North and 1.6" East of the S0 galaxy NGC 2765 (z=0.01255, d=51 Mpc from Virgo-infall corrected velocity, via NED) giving it an absolute V mag of approx. -18.4 (m-M=33.55, A_V=0.09, Schlafly & Finkbeiner 2011) and a projected distance from the host galaxy of approximately 1.4 kpc.
For more information about the ASAS-SN project see the ASAS-SN Homepage and also ASAS-SN Transients page.