[IAUC] CBET 2848: 20111001 : SUPERNOVA 2011gn IN MCG +13-5-36 = PSN J07062829+7752318

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                                                  Electronic Telegram No. 2848
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)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


SUPERNOVA 2011gn IN MCG +13-5-36 = PSN J07062829+7752318
     T. Boles, Coddenham, England, reports the discovery of an apparent
supernova (mag 18.0) on an unfiltered CCD image taken on Sept. 30.113 UT with
a 0.35-m reflector.  The new object is located at R.A. = 7h06m28s.29, Decl. =
+77o52'31".8, which is approximately 2".4 west and 20".3 north of the center
of MCG +13-05-36 = PGC 20157.  The variable was given the designation PSN
J07062829+7752318 when it was posted at the Central Bureau's TOCP webpage and
is here designated SN 2011gn based on the spectroscopic confirmation reported
below.  Additional magnitudes for 2011gn (from unfiltered CCD images unless
noted otherwise):  1989 Dec. 17, [20.5 (Digitized Sky Survey red plate; via
Boles); 1996 Dec. 12, [21.0 (Digitized Sky Survey blue plate; via Boles);
2010 Dec. 6, [19.5 (Boles); 2011 Feb. 12, [19.5 (Boles); Sept. 30.855, 17.0
(Nick D. James, Chelmsford, Essex, England; Celestron C11 telescope + ST9-XE
camera; position end figures 28s.31, 31".6).

     S. Valenti, E. Cappellaro, S. Benetti, Osservatorio Astronomico di
Padova, Istituto Nazionale di Astrofisica (INAF); M. Turatto, Osservatorio
Astronomico di Trieste, INAF; and A. Pastorello, Dipartimento di Astronomia,
Universita di Padova, on behalf of a larger collaboration, report that a
spectrogram (range 360-810 nm; resolution 2.2 nm) of PSN J07062829+7752318 =
SN 2011gn was obtained on Oct. 1.05 UT with the Ekar-Copernico 1.82-m
telescope (+ AFOSC).  Cross-correlation with a library of supernova spectra,
via the "Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J.
666, 1024), shows that the best fit is with the type-Ia supernova 2003du at
three weeks after maximum.  With a derived redshift of 0.029, the expansion
velocity measured from the minimum of Si II 635.5-nm doublet is 10000 km/s.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2011 CBAT
2011 October 1                   (CBET 2848)              Daniel W. E. Green