[IAUC] CBET 2556: 20101127 : SUPERNOVA 2010kd

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                                                  Electronic Telegram No. 2556
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 2010kd
     J. Vinko, University of Szeged; W. Zheng and A. Romadan, University of
Michigan; R. Quimby, California Institute of Technology; N. Whallon, S. B.
Pandey, Y. Fang, and C. Akerlof, University of Michigan; P. Pasque and M.
Verkinderen, Cousino High School; and J. C. Wheeler and E. Chatzopoulos,
University of Texas, on behalf of the ROTSE collaboration, report the discovery
of a new supernova (mag about 17.5) in unfiltered images taken on Nov. 14.49 UT
with the 0.45-m ROTSE-IIIb telescope at McDonald Observatory.  The new object
-- which was observed again on Nov. 16.49 at mag about 17.4, on Nov. 18.48 at
mag about 17.4, and on Nov. 22.47 at mag about 17.5 -- is located at R.A. =
12h08m01s.11, Decl. = +49o13'31".1 (equinox 2000.0; uncertainty about 1"),
which is 2".1 east and 1".8 south of the center of the presumed host galaxy
(SDSS J120800.89+491332.8).  Note that there is a fainter, uncatalogued
extended source about 2" southeast of the host galaxy that is also a possible
candidate to be the host galaxy of the new supernova.  A finding chart for the
new object can be found at the following website URL:
http://www.rotse.net/rsvp/j120801.1+491331/j120801.1+491331.jpg.  A spectrum,
obtained on Nov. 22.51 UT with the 9.2-m Hobby-Eberly Telescope (+ Marcario
Low-Resolution Spectrograph) by J. Caldwell, shows broad, weak P-Cyg features
superimposed on a blue continuum, consistent with an early type-II supernova.
If the strongest broad feature is due to H-alpha, then the redshift is z about
0.1, implying a peak absolute magnitude brighter than -20.5 (neglecting
interstellar extinction).  According to SNID (Blondin and Tonry 2007, Ap.J.
666, 1024), the spectrum is similar to that of SN 1999gi at 5 days before
maximum light at a redshift consistent with the above estimate, but no
template matches all the observed features well.  These suggest that the
supernova may be a peculiar, super-luminous event.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
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                         (C) Copyright 2010 CBAT
2010 November 27                 (CBET 2556)              Daniel W. E. Green