[IAUC] CBET 3106: 20120516 : SUPERNOVA 2012cd IN PGC 46714

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                                                  Electronic Telegram No. 3106
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 en eps.harvard.edu (alternate cbat en iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


SUPERNOVA 2012cd IN PGC 46714
     Vladimir Lipunov reports the discovery of a possible supernova (mag 15.1)
on two unfiltered CCD images (limiting mag 18.7) obtained with the auto-
detection system of the MASTER II 40-cm telescope (+ Apogee Alta U16m camera;
field-of-view 2x4 square degrees) at the Kislovodsk observatory (see website
URL http://observ.pereplet.ru) on May 6.  The new object is located at R.A. =
13h22m35s.25, Decl. = +54d48'47".7 (equinox 2000.0), which is 24" east and 18"
south of the center of PGC 46714.  Nothing is visible at this position on a
MASTER reference image from 2010 Apr. 28 (limiting mag 19.1).  The discovery
and reference images are posted at the following website URL:
http://observ.pereplet.ru/images/132235.25+544847.7.png.

     G. H. Marion and R. J. Foley, Harvard-Smithsonian Center for Astrophysics
(CfA), on behalf of the CfA Supernova Group, report that a spectrum (range
340-740 nm) of 2012cd was obtained on May 12 UT by M. Calkins 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 2012cd is a type-IIb
supernova near maximum light.  A prominent P-Cyg feature from H-alpha is
present, as well as absorption features from other Balmer-series lines and
absorption from multiple lines of He I.  The velocity of H, measured at the
absorption minima, is about 9000 km/s.  The He I velocity is about 6000 km/s.
Good fits are found to several templates of SN 1993J a few days before
maximum brightness.


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                         (C) Copyright 2012 CBAT
2012 May 16                      (CBET 3106)              Daniel W. E. Green