ASAS-SN Discovery of Two Likely Supernovae in PGC 67159 and PGC 55442

ATel #5346; T. W-S. Holoien (Ohio State), J. Brimacombe (Coral Towers Observatory), B. J. Shappee, K. Z. Stanek, C. S. Kochanek, J. Jencson, U. Basu, J. F. Beacom (Ohio State), J. L. Prieto (Princeton), D. Szczygiel, G. Pojmanski (Warsaw University Observatory), M. Dubberley, M. Elphick, S. Foale, E. Hawkins, D. Mullens, W. Rosing, R. Ross, Z. Walker (Las Cumbres Observatory)
on 30 Aug 2013; 17:13 UT
Distributed as an Instant Email Notice Transients
Credential Certification: Krzysztof Stanek (stanek.32@osu.edu)

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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 two new transient sources, both likely supernovae:

 
Object            RA(J2000)        Dec(J2000)      Disc. UT Date    Disc. V Mag 
ASASSN-13co       21:40:38.74     +06:30:36.87     2013 Aug. 29.39    16.9 
ASASSN-13cp       15:33:49.236    +21:08:21.87     2013 Aug. 30.24    16.6 

ASASSN-13co was discovered in images obtained on UT Aug. 29.39 and confirmed on Aug. 30 (V mag 16.87) with a possible earlier detection on Aug. 27. It is undetected (V > 17) on August 23 and earlier. A confirmation image (3x900 sec) was obtained by J. Brimacombe in the IR filter (close to I-band) on Aug. 30.59 with a 16-inch RCOS telescope at Coral Towers Observatory (Cairns, Australia). This figure shows the discovery subtraction residual and confirmation images in the bottom-left and bottom-right panels, respectively, with the ASAS-SN reference image in the top-left and SDSS g'-band image in the top-right. The circle has a 7.5" radius and is in the same position in each image.

ASASSN-13co is approximately 1.87" N and 2.39" W of the center of z=0.023063 (d=92 Mpc from cosmology-corrected quantities, via NED) spiral galaxy PGC 67159, giving it an absolute magnitude of approximately M_V=-18.07 (m-M=34.81, A_V=0.16, Schlafly & Finkbeiner 2011) and a projected distance from the galaxy center of approximately 1.29 kpc.

ASASSN-13cp was discovered in images obtained on UT August 30.24 with a possible detection on Aug. 24 but undetected (V > 17) on Aug. 19 and earlier. This figure shows our Aug. 24 detection and Aug. 30 discovery subtraction images in the bottom-left and bottom-right along with our reference image in the top-left and SDSS g'-band image in the top-right. The circle again has a 7.5" radius and is in the same position in each image.

ASASSN-13cp is approximately 11.81" N and 4.85" E of the center of z=0.023576 (d=100 Mpc from cosmology-corrected quantities, via NED) spiral galaxy PGC 55442, giving it an absolute magnitude of approximately M_V=-18.57 (m-M=35.01, A_V=0.16, Schlafly & Finkbeiner 2011) and a projected distance from the galaxy center of approximately 5.9 kpc.

For more information about the ASAS-SN project see the ASAS-SN Homepage and also ASAS-SN Transients page.