Electronic Telegram No. 3093
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 2012bw IN UGC 10282 = PSN J16125609+3230423
     S. Howerton, Arkansas City, KS, U.S.A.; A. J. Drake, S. G. Djorgovski,
A. Mahabal, M. J. Graham, and R. Williams, California Institute of Technology;
J. L. Prieto, Princeton University; M. Catelan, Pontificia Universidad
Catolica de Chile; R. H. McNaught, Australian National University; E. C.
Beshore and S. M. Larson, Lunar and Planetary Laboratory, University of
Arizona; and E. Christensen, Gemini Observatory, report the discovery of an
apparent supernova in public images from the Catalina Sky Survey (CSS).

 SN       2012 UT        R.A. (2000.0) Decl.      Mag.      Offset
 2012bw   Mar. 22.44   16 12 56.09  +32 30 42.3   19.0    19".0 W, 2".6 S

Nothing was visible at this position on an image from Apr. 2.45 UT (limiting
mag 20.0).  The variable was designated PSN J16125609+3230423 when it was
posted at the Central Bureau's TOCP webpage and is here designated SN 2012bw
based on the spectroscopic confirmation reported below.

     L. Tomasella, S. Benetti, E. Cappellaro, P. Ochner, A. Pastorello, M.
Turatto, and S. Valenti, Osservatorio Astronomico di Padova, Istituto
Nazionale di Astrofisica, obtained a spectrogram of 2012bw on Apr. 25.06 UT
with the Asiago 1.82-m Copernico Telescope (+ AFOSC; range 340-820 nm;
resolution 2.4 nm).  The extracted spectrum, heavily contaminated by narrow
emission lines likely originating from a nearby H II region, suggests that
this is a type-Ic supernova near maximum.  Cross-correlation with a library of
supernova spectra via the "Supernova Identification" code (SNID; Blondin and
Tonry 2007, Ap.J. 666, 1024) shows that, assuming a redshift of z = 0.0309 for
the host galaxy (average of different estimates listed in the NASA/IPAC
Extragalactic Database), 2012bw is similar to several type-Ic supernovae near
maximum at a redshift z = 0.031.  The redshift coincides with the redshift of
the host galaxy, UGC 10282 (average of different estimates listed in the
NASA/IPAC Extragalactic Database).


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2012 CBAT
2012 April 26                    (CBET 3093)              Daniel W. E. Green