[IAUC] CBET 2676: 20110312 : SUPERNOVA 2011at = PSN J09285756-1448206

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                                                  Electronic Telegram No. 2676
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 2011at = PSN J09285756-1448206
     L. Cox, J. Newton, and T. Puckett report the discovery of an apparent
supernova (mag 14.5) on an unfiltered CCD image (limiting mag 19.0) taken with
a 0.40-m reflector at Portal, AZ, U.S.A., on Mar. 10.214 UT in the course of
the Puckett Observatory Supernova Search.  The new object was designated
PSN J09285756-1448206 when posted on the Central Bureau's TOCP webpage and is
here designated SN 2011at based on the spectroscopic reports below.  SN 2011at
is located at R.A. = 9h28m57s.56, Decl. = -14d48'20".6 (equinox 2000.0), which
is 20".4 east and 6".3 north of the center of PGC 26905 = MCG -02-24-27.
Nothing is visible at this position on images taken by Puckett on Feb. 13
(limiting mag 19.1).

     F. Bufano, Istituto Nazionale di Astrofisica (INAF), Osservatorio
Astronomico di Catania; S. Benetti, INAF, Osservatorio Astronomico di Padova;
and A. Pastorello, Queen's University, Belfast, on behalf of a larger
collaboration, report that a spectrogram (range 200-500 nm) of PSN
J09285756-1448206 = 2011at was obtained on 2011 Mar. 11.81 UT with the Swift
satellite (+ UVOT).  The spectrum of 2011at is consistent with that of a
type-Ia supernova around maximum, showing strong absorption features mainly
due to Ca II H and K, Si II, Fe III, and Co III and resembling ultraviolet
spectra of SN 2005cf at similar epochs (Bufano et al. 2009, Ap.J. 700, 1456).
A multi-wavelength follow-up campaign of observing 2011at, using numerous
ground-based facilities, is in progress.

     G. H. Marion, Harvard-Smithsonian Center for Astrophysics (CfA), on
behalf of the CfA Supernova Group, report that a spectrum (range 340-740 nm)
of PSN J09285756-1448206 = 2011at was obtained on Mar. 12 UT by M. Calkins
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 the object is a
type-Ia supernova a few days before maximum light.  The velocity of the Si II
635.5-nm feature, measured at the absorption minimum, is 12100 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 March 12                    (CBET 2676)              Daniel W. E. Green