[IAUC] CBET 3330: 20121205 : SUPERNOVA 2012hg

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                                                  Electronic Telegram No. 3330
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 2012hg
[Editor's note:  this text replaces that on CBET 3328 (position correction)]
     Tianmeng Zhang and Xu Zhou, National Astronomical Observatories of China
(NAOC); and Juncheng Chen and Xiaofeng Wang, Tsinghua University (THU), China,
report the discovery of an apparent supernova (mag 18.0) on unfiltered CCD
images taken on Nov. 25.8 UT using the 0.6-m NAOC Schmidt telescope in the
course of the THU-NAOC Transient Survey (TNTS).  The object was located at
R.A. = 7h07m25s.60, Decl. = +56d18'19".2 (equinox 2000.0), which is 15".1 west
and 13".8 north of the center of the presumed host galaxy.  Nothing is visible
at this position on TNTS archival images obtained on Nov. 17 (limiting mag
about 19.5) or on Digitized Sky Survey images from the Palomar Sky Survey.
Additional approximate unfiltered TNTS magnitudes for 2012hg:  Nov. 22.8,
18.9; 28.8, 17.6; 30.65, 17.0.

     X.-L. Zhao and X.-F. Wang, Tsinghua University; J.-J. Zhang and W.-B. Xu,
Yunnan Astronimical Observatory (YNAO); and T.-M. Zhang, National Astronomical
Observatories of China, report on an optical spectrogram (range 330-880 nm)
that was obtained on Dec. 1.8 UT with the 2.4-m telescope (+ YFOSC) at the
LiJiang Gaomeigu Station of the YNAO.  The spectrum is consistent with a
normal type-Ia supernova a few days before maximum light.  Cross-correlation
with a library of supernova spectra using the "Supernova Identification" code
(SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) shows that 2012hg matches with
SN 2003du at -8 days.  Adopting a recession velocity of 11297 km/s for the
presumed host galaxy (K. Rines et al. 2000, A.J. 120, 2338), they measure the
velocity of the Si II 635.5-nm absorption feature to be about
11800 km/s.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2012 CBAT
2012 December 5                  (CBET 3330)              Daniel W. E. Green