Electronic Telegram No. 2638
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 2011L
     S. B. Pandey and A. Romadan, University of Michigan; J. Vinko, University
of Szeged; R. Quimby, California Institute of Technology; N. Whallon, B.
Sandler, W. Zheng, F. Yuan, and C. Akerlof, University of Michigan; 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 17.0) in
unfiltered images taken on Jan. 14.10 UT with the 0.45-m ROTSE-IIIb telescope
at McDonald Observatory.  The new object is located at R.A. = 23h40m11s.52,
Decl. = +27o25'42".2 (equinox 2000.0; uncertainty about 1"), which is 6".4
east and 2".2 south of the center of the host galaxy (2MASX J23401103+2725444)
that is in turn part of the underlying galaxy cluster.  A finding chart for
the object can be found at the following website URL:
http://www.rotse.net/rsvp/j234011.5+272542/j234011.5+272542.jpg.  A spectrum,
taken on Jan. 15.07 UT with the 9.2-m Hobby-Eberly Telescope (+ Marcario
Low-Resolution Spectrograph) by J. Caldwell, shows that the new object is a
type-Ia supernova, several days after maximum light.  The spectrum contains
the Si II 635.5-nm line and several other characteristic type-Ia-supernova
features.  According to SNID (Blondin and Tonry 2007, ApJ. 666, 1024), the
spectrum most resembles those of SN 1995E (at 10.0 days after maximum) and SN
1996X (at 7.8 days after maximum).  The median redshift estimate is z = 0.031.
Adopting this redshift, the velocity (from the absorption minimum of the Si II
635.5-nm feature) is 12100 km/s.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
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                         (C) Copyright 2011 CBAT
2011 January 18                  (CBET 2638)              Daniel W. E. Green