[IAUC] CBET 3370: 20130106 : SUPERNOVA 2012ij IN PGC 36194 = PSN J11401584+1727222

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                                                  Electronic Telegram No. 3370
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)
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Prepared using the Tamkin Foundation Computer Network


SUPERNOVA 2012ij IN PGC 36194 = PSN J11401584+1727222
     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 18.0) on unfiltered CCD images
taken on Dec. 29.78 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. =
11h40m15s.84, Decl. = +17d27'22".2 (equinox 2000.0), which is about 4" west
and 4" south of the center of the galaxy PGC 36194.  Nothing is visible at
this position on Digitized Sky Survey images.  The TNTS images are posted at
URL http://www.thca.tsinghua.edu.cn/~wangxf/TNTS/PSNJ11401584+1727222.jpg.
The variable was designated PSN J11401584+1727222 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2012ij based on the
spectroscopic confirmation reported below.  Additional CCD magnitudes for
2012ij:  2012 Dec. 9, [20.0 (TNTS); 31.79, 17.9 (TNTS); 2013 Jan. 5.078, R_c
= 16.6 (Massimiliano Martignoni, Magnago, Italy; 0.25-m reflector; position
end figures 15s.73, 20".0).

     G. H. Marion and P. Challis, Harvard-Smithsonian Center for Astrophysics
(CfA), on behalf of the CfA Supernova Group, report that a spectrogram (range
340-740 nm) of PSN J11401584+1727222 = SN 2012ij was obtained on Jan. 3 UT by
M. Caulkins 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 2012ij is a type-Ia supernova a few days before maximum light.  A good
fit is found to the template of the subluminous type-Ia 1991bg-like supernova
2005mz at 8 days before maximum.  The velocity of the Si II 635.5-nm
absorption feature is measured to be approximately 11900 km/s, using a
redshift of z = 0.010998 for PGC 36194 (Lu et al. 1993, Ap.J. Suppl. 88,
383; via NED).

     Jujia Zhang and Weimin Yi, 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) of 2012ij that was obtained on Jan. 5.90 UT with the 2.4-m
telescope (+ YFOSC) at the LiJiang Gaomeigu Station of the YNAO.  The
spectrum is consistent with a couple of subluminous type-Ia supernovae at 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 2012ij matches with SN 2005bl at -6 days.
Adopting a recession velocity of 3297 km/s for the host galaxy (PGC 36194;
Lu et al. 1993, Ap.J. Suppl. 88, 383), they measure the velocity of the Si II
635.5-nm absorption feature to be about 11600 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 6                   (CBET 3370)              Daniel W. E. Green