Electronic Telegram No. 3772
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 2014B IN NGC 4939 = PSN J13041770-1020012
     Further to CBET 3743, H. Kim, W. Zheng, W. Li, and A. V. Filippenko,
University of California at Berkeley; and S. B. Cenko, Goddard Space Flight
Center, report the LOSS discovery of a supernova in NGC 4939 on unfiltered
KAIT images.  The discovery observation is tabulated below:

 SN       2014 UT       R.A. (2000.0) Decl.      Mag.      Offset
 2014B    Jan. 2.60   13 04 17.70  -10 20 01.2   17.0    48".6 E, 21".7 N

Nothing was detected at this position on a KAIT image obtained on 2013 June
11.2 UT (limiting mag about 18.5).  A finding chart was posted at website URL
http://astro.berkeley.edu/~zwk/findingchart/PSN_J13041770-10200121.jpg.  The
variable was designated PSN J13041770-1020012 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2014B based on the
spectroscopic confirmation reported below.  The type-II supernova 2008aw (cf.
CBET 1279) also appeared in NGC 4939, as did SNe 1968X (IAUC 2116) and 1973J
(IAUC 2538).

     Tianmeng Zhang, National Astronomical Observatories of China (NAOC); and
Xiaofeng Wang, Tsinghua University, report on an optical spectrogram (range
370-860 nm) of PSN J13041770-1020012 = SN 2014B that was obtained on Jan. 4.88
UT with the 2.16-m telescope (+ BFOSC) at the Xinglong Station of the NAOC.
The spectrum is consistent with a type-II-P supernova 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 2014B matches with SN 2004et at +20 days from maximum light.  Adopting a
redshift of 0.01037 for the host galaxy, NGC 4939 (via Koribalski et al. 2004,
A.J. 128, 16), the absorption minimum of the H-alpha line is found to be
blue-shifted by about 7200 km/s.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2014 CBAT
2014 January 5                   (CBET 3772)              Daniel W. E. Green