[IAUC] CBET 3487: 20130423 : SUPERNOVA 2013bm IN UGC 5910 = PSN J10482657+3824079

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                                                  Electronic Telegram No. 3487
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 2013bm IN UGC 5910 = PSN J10482657+3824079
     F. Ciabattari and E. Mazzoni, Borgo a Mozzano, Italy, report the
discovery of a possible supernova (mag 17.9) on unfiltered CCD images
(limiting magnitude 19.5) obtained on Apr. 16.81 and 17.89 UT with a 0.5-m
Newtonian telescope in the course of the Italian Supernovae Search Project;
the new object is located at R.A. = 10h48m26s.57, Decl. = +38d24'07".9
(equinox 2000.0; astrometry with respect to UCAC-2 stars), which is 16" west
and 19" north of the center of the galaxy UGC 5910.  Nothing is visible at
this position on digitized plates of the Palomar Sky Survey from 1998 May 16
(F plate; limiting magnitude 20.3) and 1991 Feb. 8 (J plate; limiting mag
20.3).  The variable was designated PSN J10482657+3824079 when it was posted
at the Central Bureau's TOCP webpage and is here designated SN 2013bm based
on the spectroscopic confirmation reported below.  Additional CCD magnitudes
for 2013bm:  2013 Jan. 12, [19.2 (Ciabattari); Apr. 18.058, 17.7 (Federica
Luppi and Luca Buzzi, Varese, Italy; 0.38-m f/6.8 reflector; position end
figures 26s.60, 07".5; reference stars from CMC-14 catalogue; image posted at
website URL http://www.astrogeo.va.it/pub/TOCP/PSN_U5910.jpg); 18.480, 18.8
(Joseph Brimacombe, Cairns, Australia; 41-cm CDK telescope + infrared filter;
position end figures 26s.54, 08".2; image posted at the following website
URL:  http://www.flickr.com/photos/43846774@N02/8662138755/).

     L. Tomasella, S. Benetti, A. Pastorello, E. Cappellaro, M. Turatto, and
P. Ochner, Osservatorio Astronomico di Padova, Istituto Nazionale di
Astrofisica, report that a spectrogram (range 340-820 nm; resolution 1.3
nm), obtained on Apr. 17.94 UT with the Asiago 1.82-m Copernico Telescope
(+ AFOSC) shows that PSN J10482657+3824079 = SN 2013bm is a young type-II
supernova.  The spectrum of 2013bm shows a blue continuum with a black-body
temperature of about 10800 K.  Emission Balmer and He I 587.6-nm lines are
recovered at the recession velocity of the host galaxy (UGC 5910), 7661 km/s
(from SDSS data release 5, 2006; via NED).  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 23                    (CBET 3487)              Daniel W. E. Green