[IAUC] CBET 2857: 20111004 : SUPERNOVA 2011gr = PSN J00204598+0656052

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                                                  Electronic Telegram No. 2857
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 en eps.harvard.edu (alternate cbat en iau.org)
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Prepared using the Tamkin Foundation Computer Network


SUPERNOVA 2011gr = PSN J00204598+0656052
     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; 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
 2011gr   Sep. 18.45   0 20 45.98  + 6 56 05.2   18.3    21".7 E, 2".4 N

This variable was designated PSN J00204598+0656052 when it was posted on the
Central Bureau's TOCP webpage and is here designated SN 2011gr based on the
spectroscopic report below.  Further CCD magnitudes for 2011gr, unfiltered
unless otherwise noted:  June 28.46 UT, [20.0 (CSS); Sept. 19.468, 18.7 (J.
Brimacombe, Cairns, Australia; position end figures 45s.95, 05".1; image
posted at website URL http://www.flickr.com/photos/43846774@N02/6166997171/);
Oct. 2.092, R = 18.9 (Federica Luppi, Varese, Italy, 0.36-m f/7.9 reflector
+ Bessell R filter; position end figures 45s.94, 04".8; CMC-14 reference
stars; image posted at http://www.astrogeo.va.it/pub/TOCP/PSN_P1310401.jpg).

     L. Magill and R. Kotak, Queen's University, Belfast, report that an
optical spectrogram (range 350-900 nm) of PSN J00204598+0656052 = SN 2011gr was
obtained at the Nordic Optical Telescope (+ ALFOSC) by M. B. Nielsen on Sept.
28.97 UT; cross-correlatation with a library of supernova spectra using the
SNID software yields a best fit was with a type-Ia supernova, being similar to
SN 2003du at epochs of 20-22 days (Anupama et al. 2005, A.Ap. 429, 667).
Fitting with SNID yields a redshift of 0.068.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2011 CBAT
2011 October 4                   (CBET 2857)              Daniel W. E. Green