[IAUC] CBET 3300: 20121116 : SUPERNOVA 2012gj IN UGC 11404 = PSN J19070073+2900166

Vie Nov 16 09:29:26 ART 2012

                                                  Electronic Telegram No. 3300
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 2012gj IN UGC 11404 = PSN J19070073+2900166
     Zhijian Xu (Nanjing, Jiangsu, China) and Xing Gao (Urumqi, Xinjiang,
China) report the discovery of an apparent supernova (mag approximately 17.4)
on an unfiltered 40-s CCD survey image (limiting mag about 18.5) taken by
Xing Gao in the course of the Xingming Observation Sky Survey at Mt. Nanshan
around Nov. 12.551 UT using a 36-cm Celestron C14 Schmidt-Cassegrain telescope.
The new object is approximately located at R.A. = 19h07m00s.73, Decl. =
+29d00'16".6 (equinox 2000.0), which is about 34".5 west and 6".5 south of the
center of UGC 11404.  Nothing is visible at this position on a Digitized Sky
Survey image from 1987 June 21 (limiting mag about 19.8; no bandpass
specified).  The discovery images are posted at the following website URL:
http://www.xjltp.com/XOSS/XM54ZX/XM54ZX.htm.  The variable was designated PSN
J19070073+2900166 when it was posted at the Central Bureau's TOCP webpage
and is here designated SN 2012gj based on the spectroscopic confirmation
reported below.  Additional CCD magnitudes for 2012gj:  Oct. 30, [18.7 (Gao);
Nov. 9, [19.0 (Gao); 13.058, 16.9 (R. A. Koff, Bennett, CO, USA; Meade 0.25-m
f/10 reflector + Apogee U-47 camera; limiting magnitude 19.0; position end
figures 00s.66, 16".9; UCAC3 reference stars); 13.136, 17.7 (J. Brimacombe,
Cairns, Australia; luminance filter; position end figures 00s.68, 17".2;
image posted at URL http://www.flickr.com/photos/43846774@N02/8187102022/);
14.535, 16.9 (Xu and Gao; position end figures 00s.70, 17".2).

     S. Zaggia, L. Tomasella, S. Benetti, and A. Pastorello, Osservatorio
Astronomico di Padova, Istituto Nazionale di Astrofisica, report that optical
spectroscopy (range 450-820 nm; resolution 1.3 nm) obtained on Nov. 15.77 UT
with the Asiago 1.82-m Copernico Telescope (+ AFOSC) shows that PSN
J19070073+2900166 = SN 2012gj is a type-II supernova at redshift, z, around
0.013 (Haynes and Giovanelli 1997, A.J. 113, 1197; via NED database).  A good
match is found with several type-II supernovae about 10 days after the core
collapse.  An ejecta expansion velocity of about 14000-15000 km/s is derived
from the minimum of the very broad, P-Cyg profile H-alpha line.  Together with
the Balmer lines, Fe II features are also detected.  The Asiago classification
spectra are posted at 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
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                         (C) Copyright 2012 CBAT
2012 November 16                 (CBET 3300)              Daniel W. E. Green