Electronic Telegram No. 2917
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 2011ig = PSN J01055465-1220486
     A. J. Drake, S. G. Djorgovski, M. J. Graham, A. Mahabal, and R. Williams,
California Institute of Technology; J. L. Prieto, Princeton University; M.
Catelan, Pontificia Universidad Catolica de Chile; 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 unfiltered Catalina Sky Survey (CSS) images:

 SN       2011 UT       R.A. (2000.0) Decl.      Mag.      Offset
 2011ig   Nov. 17.21   1 05 54.65  -12 20 48.6   16.9    0".7 W, 3".7 S

The variable was designated PSN J01055465-1220486 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2011ig based on the
spectroscopic confirmation reported below.  Additional CCD magnitudes for
2011ig:  Oct. 30.28 UT, [17.5 (CSS); Nov. 20.316, 17.5 (J. Brimacombe, Cairns,
Australia; luminance filter; position end figures 54s.65, 50".2; image posted
at website URL http://www.flickr.com/photos/43846774@N02/6375756043/).

     S. Valenti, A. Pastorello, S. Benetti, L. Tomasella, F. Bufano, and P.
Ochner, Istituto Nazionale di Astrofisica, Osservatorio Astronomico di Padova,
on behalf of a larger collaboration, report that a spectrogram of PSN
J01055465-1220486 = SN 2011ig, obtained on Nov. 20.89 UT with the 1.82-m
Copernico Telescope (+ AFOSC; range 340-790 nm, resolution 2.2 nm), suggests
that it is a 1991T-like type-Ia supernova.  Cross-correlation with a library
of supernova spectra via the "Supernova Identification" code (SNID; Blondin
and Tonry 2007, Ap.J. 666, 1024) indicates that 2011ig is similar to SN
1999aa (Garavini et al. 2004, A.J. 128, 387) around maximum light.  Assuming
a redshift of z = 0.065, the ejecta velocity deduced from the minimum of the
Si II 635-nm line is about 13500 km/s.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2011 CBAT
2011 November 23                 (CBET 2917)              Daniel W. E. Green