[IAUC] CBET 3292: 20121109 : SUPERNOVA 2012gd = PSN J01514770+2116206

Vie Nov 9 08:36:39 ART 2012

                                                  Electronic Telegram No. 3292
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 2012gd = PSN J01514770+2116206
     V. Lipunov, Sternberg Astronomical Institute (SAI), Lomonosov Moscow
State University, reports the discovery by P. Balanutsa of an apparent
supernova (magnitude 16.9) on two unfiltered survey images (180-s exposures)
taken with the 0.40-m f/2.5 MASTER-Kislovodsk robotic telescope on Oct. 23.890
and 23.908 UT.  The new object is located at R.A. = 1h51m47s.70, Decl. =
+21d16'20".6 (equinox 2000.0), which is 31".5 east and 6".9 north of the core
of the galaxy PGC 1646513 = 2MASX J01514544+2116137, and is 7".0 east and
15".7 north of another nearby galaxy (SDSS J015147.20+211604.9).  D. Denisenko
and E. Gorbovskoy (SAI) add that the variable was already detected on three
MASTER-Kislovodsk images from Oct. 22 (at magnitude 17.1-16.8) and on one image
from Oct. 24.77; it is marginally present on MASTER-Amur images taken on Oct.
17.  The variable was designated PSN J01514770+2116206 when it was posted at
the Central Bureau's TOCP webpage and is here designated SN 2012gd based on the
spectroscopic confirmation reported below.  Additional unfiltered CCD
magnitudes for 2012gd:  Oct. 5.540, [18.5 (MASTER-Amur image; via Lipunov et
al.); Nov. 4.877, 17.4 (Denisenko, Gorbovskoy, and Lipunov; MASTER-Kislovodsk
telescope; images viewable at website URL http://tinyurl.com/d4k5rnh); Nov.
7.200, 18.0 (R. A. Koff; Bennett, CO, USA; Meade 0.25-m f/10 reflector +
Apogee U-47 camera; limiting magnitude 19.9; eleven stacked 240-s images;
position end figures 47s.73, 21".0; UCAC3 reference stars; image can be viewed
via website URL http://tinyurl.com/awelvs5).

     L. Tomasella, S. Benetti, E. Cappellaro, A. Pastorello, M. Turatto, and
M. Fiaschi Osservatorio Astronomico di Padova, Istituto Nazionale di
Astrofisica, report that optical spectroscopy (range 340-820 nm; resolution
1.3 nm), obtained on Nov. 6.02 UT with the Asiago 1.82-m Copernico Telescope
(+ AFOSC range 350-820 nm, resolution 1.3nm), indicates that PSN
J01514770+2116206 = SN 2012gd is a type-Ia supernova about ten days after
maximum light at redshift z about 0.055.  The expansion velocity, as deduced
from the position of the Si II 635.5-nm absorption, is about 10000 km/s.
The Asiago classification spectra are posted at the following website URL
http://graspa.oapd.inaf.it; classification was made via GELATO (Harutyunyan
et al. 2008, A.Ap. 488, 383) and SNID (Blondin and Tonry 2007, Ap.J. 666,
1024).


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

                         (C) Copyright 2012 CBAT
2012 November 9                  (CBET 3292)              Daniel W. E. Green