Electronic Telegram No. 3145
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 2012ct
     Tomoki Morokuma, Institute of Astronomy, University of Tokyo; Nozomu
Tominaga and Kensho Mori, Konan University; Masaomi Tanaka and Nobuharu Ukita,
National Astronomical Observatory of Japan; Shigeyuki Sako, Noriyuki Matsunaga,
Mamoru Doi, Naoto Kobayashi, Takashi Miyata, Nobuyuki Ienaka, Yoshikazu Nakada,
Tsutomu Aoki, Takao Soyano, Kenichi Tarusawa, and Hiroyuki Mito, Institute of
Astronomy, University of Tokyo; Michael W. Richmond, Rochester Institute of
Technology; and Yuji Urata, National Central University; on behalf of the Kiso
Supernova Survey (KISS) project, report the discovery of an apparent supernova
(mag 18.0) on a g-band CCD image (limiting mag 20.0) taken on May 22.50 UT
with the Kiso Wide Field Camera (KWFC; field-of-view 2.1 deg x 2.1 deg) on the
1.05-m Kiso Schmidt telescope at the Kiso Observatory.  The new object is
located at R.A. = 16h32m13s.92, Decl. = +38d39'25".1 (equinox 2000.0), which
is 2".7 east and 5".1 north of the presumed host galaxy (SDSS
J163213.74+383920.1; at z = 0.0393, from the Sloan Digital Sky Survey
database).  Nothing is seen at this position on reference images taken before
May 12 (limiting mag 20.7).  The new object was marginally detected in a g-band
image taken on May 18.75, as well as in gri-band images with the Lulin 1-m
telescope in Taiwan after the discovery (but no additional magnitudes were
provided).  The discovery and reference images from May 22 and Apr. 27,
respectively, have been posted by the KISS team at the following website URL:
http://www.ioa.s.u-tokyo.ac.jp/kisohp/KISS/images/iauc_J163213.92+383925.1.jpg

     E. S. Walker, Scuola Normale Superiore (SNS), Pisa; P. A. Mazzali,
Max-Planck-Institut fuer Astrophysik, Garching, and Istituto Nazionale di
Astrofisica (INAF), Padova; E. Pian, SNS, Pisa, and INAF, Trieste; Masaomi
Tanaka, National Astronomical Observatory of Japan; Tomoki Morokuma, Institute
of Astronomy, University of Tokyo; and Nozomu Tominaga and Kensho Mori, Konan
University, report that they obtained a CCD spectrogram (range 350-800 nm) of
2012ct using the DOLORES spectrograph on the Telescopio Nazionale di Galileo
situated on La Palma on May 24.9 UT.  The spectrum shows a series of hydrogen
Balmer features, implying that 2012ct is a type-II supernova.  The hydrogen
features show strong emission components.  SN 2012ct is situated in the galaxy
SDSS J163213.74+383920.0 and shows a redshift of lines consistent with the
redshift of the host z = 0.039 (from Sloan Digital Sky Survey catalogue 3.C,
dated 2004).  Using the publicly available SNID code (Blondin and Tonry 2007,
Ap.J. 666, 1024), 2012ct appears most similar to the type-II supernovae
2005cs, 1999em, and 2004et around maximum light.


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

                         (C) Copyright 2012 CBAT
2012 June 19                     (CBET 3145)              Daniel W. E. Green