Electronic Telegram No. 3523
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 2013ck
     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
 2013ck   May  8.28   15 24 29.07  +48 32 54.6   17.5    1".1 W, 1".8 N

Nothing was visible at this position on a CSS image from Apr. 15.43 UT
(limiting mag 20.2).

     L. Tomasella, S. Benetti, A. Pastorello, 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 May 9.04 UT with the Asiago 1.82-m Copernico Telescope (+ AFOSC),
shows that 2013ck is a type-Ia supernova at redshift z about 0.049.  A good
match is found with several normal type-Ia supernovae a few days before
maximum light.  The expansion velocity, as deduced from the position of the
minimum of the Si II 635.5-nm absorption, is about 10300 km/s.  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      superseded by text appearing later in the printed IAU Circulars.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 13                      (CBET 3523)              Daniel W. E. Green