[IAUC] CBET 2905: 20111122 : SUPERNOVA 2011hv IN NGC 7589 = PSN J23181655+0015431

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                                                  Electronic Telegram No. 2905
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 2011hv IN NGC 7589 = PSN J23181655+0015431
     F. Ciabattari, S. Donati, E. Mazzoni, G. Petroni, and M. Rossi, Borgo a
Mozzano Italy, report the discovery of an apparent supernova (mag 18.1) on
unfiltered CCD images obtained on Nov. 17.73 and 18.79 UT with a 0.5-m
Newtonian reflector in the course of the Italian Supernovae Search Project,
the new object being located at R.A. = 23h18m16s.55, Decl. = +0d15'43".1
(equinox 2000.0; astrometry with respect to UCAC2-catalogue stars), which is
14" east and 4" north of the center of the galaxy NGC 7589.  Nothing is
visible at this position in their images from September (limiting magnitude
19.1).  The variable was designated PSN J23181655+0015431 when it was posted
at the Central Bureau's TOCP webpage and is here designated SN 2011hv based
on the spectroscopic confirmation reported below.  Additional magnitudes for
2011hv:  1988 Aug. 17, [20.3 (Palomar Sky Survey via Digitized Sky Survey;
J plate; via Ciabattari); 1991 Sept. 4, [20.3 (Palomar Sky Survey, F plate;
via Ciabattari); 2011 Nov. 19.088, 17.4 (Joseph Brimacombe, Cairns, Australia;
luminance filter; position end figures 16s.50, 42".7; image posted at website
URL http://www.flickr.com/photos/43846774@N02/6363363975/).

     S. Valenti, A. Pastorello, S. Benetti, L. Tomasella, F. Bufano, and P.
Ochner, Istituto Nazionale di Astrofisica, Osservatorio Astronomico di Padova,
on behalf of a larger collaboration, report that a low-signal-to-noise
spectrogram of PSN J23181655+0015431 = SN 2011hv, obtained on Nov. 19.72 UT
with the 1.82-m Copernico Telescope (+ AFOSC; range 340-790 nm, resolution
2.2 nm), indicates that it is a type-Ia supernova around maximum.  Cross-
correlation with a library of supernova spectra via the "Supernova
Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) indicates
that it is similar to SN 1999aw (Strolger et al. 2002, A.J. 124, 2905) around
maximum.  Adopting a recessional velocity of 8938 km/s (Impey et al. 1996,
Ap.J. Suppl. 105, 209; via NED), the ejecta velocity deduced from the minimum
of the Si II 635-nm line is about 12000 km/s.


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                         (C) Copyright 2011 CBAT
2011 November 22                 (CBET 2905)              Daniel W. E. Green