Electronic Telegram No. 2689
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 2011bg = PSN J11561431+2521119
     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, Carnegie Observatories; 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 Catalina Real-time Transient Survey's discovery of an apparent
supernova in public images from the Catalina Sky Survey (CSS).

 SN       2011 UT        R.A. (2000.0) Decl.      Mag.      Offset
 2011bg   Mar. 26.34   11 56 14.31  +25 21 11.9   16.7    1" N

This variable was designated PSN J11561431+2521119 when posted at the
Central Bureau's TOCP webpage and is here designated SN 2011bg based on
the spectroscopic report below.  Further unfiltered CCD magnitudes for
2011bg:  Mar. 5.33 UT, [18.4 (CSS); 28.31, 16.3 (remotely using a 0.5-m
LB-1 telescope at Rodeo, NM, U.S.A.).

     G. H. Marion, Harvard-Smithsonian Center for Astrophysics (CfA), on
behalf of the CfA Supernova Group, reports that a spectrum (range 340-740 nm)
of PSN J11561431+2521119 = SN 2011bg was obtained on Apr. 2 UT by Marion 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 2011bg is a type-Ia
supernova of the 1991T-like sub-class at a few days before maximum light.
Using a redshift of z = 0.0322, measured from host-galaxy emission lines, the
velocity of the Si II 635.5-nm feature is estimated to be approximately 10500
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      superseded by text appearing later in the printed IAU Circulars.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 April 10                    (CBET 2689)              Daniel W. E. Green