Electronic Telegram No. 3383
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 2012ik = PSN J07352691+5152504
     Li Zhou, Xiaofeng Wang, and Juncheng Chen, Tsinghua University (THU); and
Tianmeng Zhang and Xu Zhou, National Astronomical Observatories of China
(NAOC), report the discovery of an apparent supernova (mag 19.4) on unfiltered
CCD images taken on 2012 Dec. 23.80 UT using the 0.6-m NAOC Schmidt telescope
in the course of the THU-NAOC Transient Survey (TNTS).  The new object is
located at R.A. = 7h35m26s.91, Decl. = +51d52'50".4 (equinox 2000.0), which
is about 25".6 east and 17".4 north of the center of the galaxy 2MASX
J07352516+5152330.  Nothing is visible at this position on a Digitized Sky
Survey image from the Palomar Sky Survey.  The TNTS discovery image is posted
at URL http://www.thca.tsinghua.edu.cn/~wangxf/TNTS/PSNJ07352691+5152504.png.
The variable was designated PSN J07352691+5152504 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2012ik based on the
spectroscopic confirmation reported below.  Additional unfiltered CCD
magnitudes for 2012ik:  2012 Nov. 19, [20.0 (TNTS); 2013 Jan. 5.80, 19.7
(TNTS); 7.934, 19.1 (F. Luppi and L. Buzzi, Varese, Italy; 0.38-m reflector;
position end figures 26s.86, 50".4; NOMAD catalogue reference stars; image
posted at URL http://www.astrogeo.va.it/pub/TOCP/PSN_J07352691+5152504.jpg);
8.239, 20.2 (R. A. Koff, Bennett, CO, USA; 0.25-m reflector; limiting mag
20.8; position end figures 26s.90, 50".2; reference UCAC3; image posted at
http://antelopehillsobservatory.org/SNpictures/PSNJ07352691+5152504final.jpg).

     Jujia Zhang, Yunnan Astronimical Observatory (YNAO); Xulin Zhao and
Xiaofeng Wang, Tsinghua University; and Tianmeng Zhang, National Astronomical
Observatories of China, report on an optical spectrogram (range 340-850 nm)
that was obtained on 2013 Jan. 12.79 UT with the 2.4-m telescope (+ YFOSC) at
the LiJiang Gaomeigu Station of the YNAO.  The spectrum is consistent with a
subluminous type-Ia supernova at about two weeks after 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 2012ik matches well with SN 1997cn at +15 days.  Adopting a redshift of
0.064 (from the SNID fit) for the host galaxy (2MASX J07352516+51523304) they
measure the velocity of the Si II 635.5-nm absorption feature to be about
8700 km/s.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2013 CBAT
2013 January 15                  (CBET 3383)              Daniel W. E. Green