Electronic Telegram No. 3516
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 2013cf = PSN J11343649+5453244
     Ron Arbour, South Wonston, Hants, U.K., reports the discovery of an
apparent supernova (mag 18.1) on an unfiltered CCD image taken on Apr. 29.954
UT using a 35-cm f/6 Schmidt-Cassegrain telescope (+ SXVF H9 camera) in the
course of his supernova patrol; the new object is located at R.A. =
11h34m36s.49, Decl. = +54d53'24".4 (equinox 2000.0), which is 5" west and 5"
south of the galaxy PGC 213858.  Nothing is visible at this position on
Palomar Sky Survey images from the Digitized Sky Survey taken on 1993 Apr.
25 (limiting red mag about 20.0) and 1994 Apr. 14 (limiting blue mag about
19.2).  The variable was designated PSN J11343649+5453244 when it was posted
at the Central Bureau's TOCP webpage and is here designated SN 2013cf based
on the spectroscopic confirmation reported below.  Additional CCD magnitudes
for 2013cf:  Apr. 30.292, 18.0 (J. Brimacombe, Cairns, Australia; using a
51-cm RCOS telescope + luminance filter located at the New Mexico Skies
observatory near Mayhill, NM, U.S.A.; position end figures 36s.45, 23".2;
image posted at URL http://www.flickr.com/photos/43846774@N02/8697915330/);
30.852, 17.4 (Nick James, Chelmsford, Essex, England; Celestron 11 telescope
+ ST9XE camera; position end figures 36s.39, 23".2; UCAC-3 reference stars);
May 1.875, 18.0 (Ron Arbour, South Wonston, U.K.; position end figures 36s.42,
23".7).

     L. Tomasella, A. Pastorello, P. Ochner, S. Benetti, E. Cappellaro, and M.
Turatto, Osservatorio Astronomico di Padova, Istituto Nazionale di Astrofisica,
report that an optical spectrogram (range 340-820 nm; resolution 1.3 nm),
obtained on May 4.90 UT with the Asiago 1.82-m Copernico Telescope (+ AFOSC),
shows that PSN J11343649+5453244 = SN 2013cf is a type-II supernova.  The
spectrum shows Balmer emissions with P-Cyg profiles.  From the positions of
the H-alpha and H-beta minima, an expansion velocity of about 7500 km/s is
derived, assuming a recessional velocity of 5794 km/s for the host galaxy, PGC
213858 (from SDSS Data Release 3, 2004; via NED).  The best match is found
with the type-IIP supernova 2004et (Sahu et al. 2006, MNRAS 372, 1315; Maguire
et al. 2010, MNRAS 404, 981) about 10-15 days after the explosion.  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 May 11                      (CBET 3516)              Daniel W. E. Green