Electronic Telegram No. 3453
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 2013aw IN PGC 91020 = PSN J10305847+2004529
     A. J. Drake, S. G. Djorgovski, M. J. Graham, A. Mahabal, and R. Williams,
California Institute of Technology; J. L. Prieto, Princeton University; M.
Catelan, Pontificia Universidad Catolica de Chile; and S. M. Larson and E.
Christensen, Lunar and Planetary Laboratory, University of Arizona, report the
Catalina Real-time Transient Survey discovery of an apparent supernova in
unfiltered Catalina Sky Survey (CSS) images:

 SN       2013 UT        R.A. (2000.0) Decl.      Mag.      Offset
 2013aw   Mar. 11.30   10 30 58.47  +20 04 52.9   20.3   6".5 E, 2".1 S

The variable was designated PSN J10305847+2004529 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2013aw based on the
spectroscopic confirmation reported below.  Additional CCD magnitudes for
2013aw:  2012 Mar. 16, [21.5 (CSS); 2013 Mar. 12.251, 18.2 (Joseph Brimacombe,
Cairns, Australia; remotely with a 51-cm RCOS telescope + luminance filter
located at the New Mexico Skies observatory near Mayhill, NM, U.S.A.;
position end figures 58s.35, 53".4; image posted at the following website URL:
http://www.flickr.com/photos/43846774@N02/8553117792/).

     L. Tomasella, A. Pastorello, S. Benetti, E. Cappellaro, P. Ochner, and M.
Turatto, Osservatorio Astronomico di Padova, Istituto Nazionale di Astrofisica,
report that optical spectroscopy (range 340-820 nm; resolution 1.3 nm),
obtained on Mar. 15.88 UT with the Asiago 1.82-m Copernico Telescope (+ AFOSC),
shows that PSN J10305847+2004529 = SN 2013aw is a type-II supernova.  The
low-S/N spectrum shows narrow H_alpha, at z = 0.026 (as given for the host
galaxy, PGC 91020, via SDSS Data Release 6, 2007; via NED) superposed on a
broader component, suggesting that it is a type-II supernova a few days after
explosion.  The poor spectral resolution does not allow determination of
whether or not the narrow H_alpha feature is from the circumstellar medium or
from an underlying H II region.  The Asiago classification spectra are posted
at website URL http://graspa.oapd.inaf.it; classification was made via GELATO
(Harutyunyan et al. 2008, A.Ap. 488, 383) and SNID (Blondin and Tonry 2007,
Ap.J. 666, 1024).


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2013 CBAT
2013 April 3                     (CBET 3453)              Daniel W. E. Green