Electronic Telegram No. 3524
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 2013cl
     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
 2013cl   May  3.45   16 19 31.59  +24 47 11.3   17.9    27".4 E, 18".2 S

Additional CSS magnitudes for 2013cl:  Apr. 8.39 UT, [20.0; May 13.40, 18.4.

     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 9.09 UT with the Asiago 1.82-m Copernico Telescope (+ AFOSC),
shows that 2013cl is a type-Ia supernova at redshift z about 0.059.  A good
match is found with the normal type-Ia supernova 2003du (Stanishev et al. 2007,
A.Ap. 416, 1057) at about 10-12 days after maximum light.  The expansion
velocity, as deduced from the position of the minimum of the Si II 635.5-nm
absorption, is about 10100 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      superseded by text appearing later in the printed IAU Circulars.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 3524)              Daniel W. E. Green