2012CBET.3017....1D

A. J. Drake, S. G. Djorgovski, M. J. Graham, A. Mahabal, and R. Williams, California Institute of Technology; J. L. Prieto, Princeton University; M. Catelan, Pontificia Universidad Catolica de Chile; E. C. Beshore and S. M. Larson, Lunar and Planetary Laboratory, University of Arizona; and E. Christensen, Gemini Observatory, report the discovery of an apparent supernova in unfiltered Catalina Sky Survey (CSS) images:

---------------------------------------------------------------------------— SN 2011 UT R.A. (2000.0) Decl. Mag. Offset ---------------------------------------------------------------------------— 2011kc Dec. 28.40 10 35 51.00 +41 09 59.4 17.6 1" north ---------------------------------------------------------------------------—

The variable was designated TCP J10355100+4109594 when it was posted at the Central Bureau's TOCP webpage and is here designated SN 2011kc based on the spectroscopic confirmation reported below.

Spectroscopic confirmation was obtained with the Palomar 5-m reflector (+ DSBS) on 2012 Jan. 16 UT; a spectrogram (range 400-800 nm) was compared with a library of spectra using the "Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024), showing that TCP J10355100+4109594 = 2011kc best matches the type-Ia supernova 2003du at two weeks past maximum.

Further CCD magnitudes for 2011kc (unfiltered unless noted otherwise): 2011 June 9.19 UT, [20.9 (CSS); Jan. 31.262, 18.0 (R. A. Koff, Bennett, CO, USA; Meade 0.25-m f/10 reflector + Apogee AP-47p camera; limiting mag 20.0; position end figures 50s.94, 59".9; UCAC3 reference stars); 31.493, 17.7 (Joseph Brimacombe, Cairns, Australia; remotely using a 51-cm RCOS telescope + STL11K camera + luminance filter at the New Mexico Skies Observatory near Mayhill, NM, U.S.A.; position end figures 51s.01, 10'00".0; image posted at website URL http://www.flickr.com/photos/43846774@N02/6612017583/); 2012 Jan. 23.32, 18.4 (CSS); Feb. 1.43, 18.8 (CSS).