Electronic Telegram No. 2627
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 2011D IN UGC 2498
     Further to CBET 2596, A. Narla, S. B. Cenko, W. Li, and A. V. Filippenko
report the Lick Observatory Supernova Search discovery of an apparent
supernova on unfiltered KAIT images, as tabulated below.  An independent
discovery was later reported by the CRTS group (cf. CBET 2619; 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,
Carnegie Observatories; 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) via public images from the
Catalina Sky Survey (CSS).

 2011 UT        R.A. (2000.0) Decl.     Mag.      Offset            Observers
 Jan. 5.09    3 02 14.58  +17 20 58.9   18.2   33".8 E, 14".7 N     CSS
 Jan. 6.30    3 02 14.53  +17 20 58.3   18.2   34".4 E, 14".8 N     KAIT

Additional magnitudes for 2011D:  2010 Dec. 8.32 UT, [19.3 (KAIT); 10.19,
[19.4 (CSS); 2011 Jan. 7.21, 18.2 (KAIT); 8.13, 17.8 (S. Howerton, remotely
with the LB-1 0.6-m telescope near Rodeo, NM, U.S.A.).  Drake notes that the
presumed host galaxy, UGC 2498, has redshift z = 0.0231.

     G. H. Marion and P. Challis, Harvard-Smithsonian Center for Astrophysics
(CfA), on behalf of the CfA Supernova Group, report that a spectrum (range
340-740 nm) was obtained of 2011D on Jan. 8 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 2011D is a type-IIb
supernova a few days before maximum light.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2011 CBAT
2011 January 9                   (CBET 2627)              Daniel W. E. Green