[IAUC] CBET 3067: 20120325 : SUPERNOVA 2012bi IN UGC 7217 = PSN J12130023+2516574

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                                                  Electronic Telegram No. 3067
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 2012bi IN UGC 7217 = PSN J12130023+2516574
     D. Rich, Hampden, ME, USA, reports his discovery of an apparent supernova
(mag about 16.0) on unfiltered CCD frames (limiting mag 19.0) taken with a
0.41-m reflector on Mar. 21.150 and 22.143 UT.  The new object is located at
R.A.= 12h13m00s.23, Decl. = +25o16'57".4 (equinox 2000.0), which is about 0".5
east and 3".5 north of the center of UGC 7217.  The variable was designated
PSN J12130023+2516574 when it was posted at the Central Bureau's TOCP webpage
and is here designated SN 2012bi based on the spectroscopic confirmation
reported below.
     An apparent independent discovery of 2012bi by S. Howerton from public
unfiltered CCD images posted by the Catalina Sky Survey (CSS) was subsequently
reported to the Central Bureau via the TOCP by Andrew Drake (whose group
formally includes 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) -- although their reported
position is some distance away from that reported by other observers for
2012bi.  Their discovery magnitude on Mar. 3.27 was 18.9, and their position
end figures are 00s.57, 51".1 (no offset provided).
     Additional magnitudes for 2012bi (CCD and unfiltered unless noted
otherwise):  1994 Feb. 14, [21.0 (digital images from Palomar Sky Survey, red
plate; via Rich); 1996 May 13, [20.5 (Palomar Sky Survey, blue plate; via
Rich); 2011 Feb. 23.193, [19.0 (Rich); 2012 Feb. 26.44, [20.0 (CSS); Mar.
22.838, 15.7 (Nick James, Chelmsford, Essex, England; C11 telescope + ST9XE
camera; red magnitude; position end figures 00s.22, 57".3; UCAC-3 reference
stars; variable located just north of galaxy center and in plane of the
edge-on galaxy); 22.882, 17.1 (Paolo Corelli, Pagnaco, Italy; 0.45-m f/4.5
telescope; position end figures 00s.22, 57"; limiting mag 19.0; nothing
visible on red POSS plate to limiting mag 20); 23.234, 16.1 (J. Brimacombe,
Cairns, Australia; remotely using a 51-cm RCOS telescope + STL11K camera +
luminance filter at the New Mexico Skies Observatory near Mayhill, NM,
U.S.A.; position end figures 00s.25, 57".2; image posted at website URL
http://www.flickr.com/photos/43846774@N02/7010245925/).

     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 J12130023+2516574 = 2012bi was obtained on Mar. 24 UT by P. Berlind 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 2012bi is a type-Ia
supernova about one week after maximum light.  A good fit is found to the
template of the normal type=Ia supernova 2004ef at +8 days.


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

                         (C) Copyright 2012 CBAT
2012 March 25                    (CBET 3067)              Daniel W. E. Green