Electronic Telegram No. 3152
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
CBAT Director:  Daniel W. E. Green; Hoffman Lab 209; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
e-mail:  cbatiau@eps.harvard.edu (alternate cbat@iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


SUPERNOVA 2012da IN PGC 83768 = PSN J13023366+2726113
     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; and S. M. Larson and E.
Christensen, Lunar and Planetary Laboratory, University of Arizona, report the
discovery of an apparent supernova in unfiltered Catalina Sky Survey (CSS)
images:

 SN       2012 UT        R.A. (2000.0) Decl.      Mag.      Offset
 2012da   June 18.24   13 02 33.66  +27 26 11.3   16.8    20".2 W, 10".7 S

The variable was designated PSN J13023366+2726113 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2012da based on the
spectroscopic confirmation reported below.  Additional CCD magnitudes for
2012da:  June 10.19 UT, [19.5 (CSS); 18.953, 16.4 (Nick James, Chelmsford,
Essex, England; C11 telescope + ST9XE camera); 19.185, 16.5 (Joseph Brimacombe,
Cairns, Australia, remotely using a 51-cm RCOS reflector + STL11K camera at
the New Mexico Skies Observatory near Mayhill, NM, U.S.A.; luminance filter
presumed; position end figures 33s.56, 12".2; image posted at website URL
http://www.flickr.com/photos/43846774@N02/7404022044/).

     G. H. Marion, Harvard-Smithsonian Center for Astrophysics (CfA), on
behalf of the CfA Supernova Group, reports that a spectrogram (range 340-740
nm) of PSN J13023366+2726113 = 2012da was obtained on June 19 UT by L. Macri
with the F. L. Whipple Observatory 1.5-m telescope (+ FAST).  Cross-
correlation with a library of supernova spectra using the "Supernova
Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) shows
that 2012da is a type-Ia supernova several days before maximum light.  A good
fit is found to the template of SN 2003du at 11 days before maximum.  The
velocity of the Si II 635.5-nm absorption feature is measured to be
approximately 12000 km/s, using a redshift of z = 0.018012 for PGC 83768
(Castander et al. 2001, A.J. 121, 2331; via NED).


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2012 CBAT
2012 June 21                     (CBET 3152)              Daniel W. E. Green