[IAUC] CBET 2901: 20111116 : SUPERNOVA 2011hr IN NGC 2691 = PSN J08544603+3932161

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                                                  Electronic Telegram No. 2901
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 2011hr IN NGC 2691 = PSN J08544603+3932161
     Further to CBET 2837, I. Nayak, S. B. Cenko, W. Li, and A. V. Filippenko
report the LOSS discovery of an apparent supernova on unfiltered KAIT images:

 SN       2011 UT       R.A. (2000.0) Decl.      Mag.      Offset
 2011hr   Nov. 8.54    8 54 46.03  +39 32 16.1   16.9    3".4 W, 3".7 S

This variable was designated PSN J08544603+3932161 when it was posted on the
Central Bureau's TOCP webpage and is here designated SN 2011hr based on the
spectroscopic confirmation reported below.  Additional CCD magnitudes for
2011hr (unfiltered unless noted otherwise):  Oct. 12.53 UT, [18.5 (KAIT); Nov.
9.58, 17.1 (KAIT); Nov. 10.111, 16.1 (Federica Luppi and Luca Buzzi, Varese,
Italy; 0.38-m f/6.8 reflector; position end figures 46s.07, 16".2; reference
stars from the CMC-14 catalogue; image posted at the following website URL:
http://www.astrogeo.va.it/pub/TOCP/PSN_N2691.jpg); Nov. 10.398, R = 16.0 (J.
Brimacombe, Cairns, Australia; position end figures 46s.14, 16".6; image
posted at website URL http://www.flickr.com/photos/43846774@N02/6332304551/).

     T.-M. Zhang, National Astronomical Observatories of China; J.-J. Zhang,
Yunnan Astronomical Observatory of China (YNAO); and X.-F. Wang, Tsinghua
Center for Astrophysics, Tsinghua University, report on an optical spectrogram
(range 350-700 nm) of PSN J08544603+3932161 = SN 2011hr that was obtained on
Nov. 10.9 UT with the YNAO 2.4-m telescope (+ YFOSC) at LiJiang Gaomeigu
Station.  The spectrum is very blue, consistent with a type-Ia supernova of
the 1991T-like subclass at about one week before maximum light, with Fe lines
dominating.  Cross-correlation with a library of supernova spectra using the
"Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666,
1024) shows that the spectrum of 2011hr matches that of SN 1997br at -7 days.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2011 CBAT
2011 November 16                 (CBET 2901)              Daniel W. E. Green