Electronic Telegram No. 3589
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 2013dz
     G. Dhungana, Southern Methodist University; J. M. Silverman, University
of Texas; W. Zheng, University of California at Berkeley; R. Kehoe and F. V.
Ferrante, Southern Methodist University; J. Vinko, University of Szeged; G. H.
Marion, University of Texas; R. Quimby, Kavli IPMU, University of Tokyo; F.
Yuan, Australian National University; J. C. Wheeler, University of Texas; and
C. Akerlof, University of Michigan, on behalf of the ROTSE collaboration,
report the discovery of a new supernova (mag about 16.2) in unfiltered images
taken on July 11.42 UT with the 0.45-m ROTSE-IIIb telescope at McDonald
Observatory.  The transient was observed again at similar brightness on July
12 and a little brighter (mag about 16) on July 13.  The new object is located
at R.A. = 02h58m24s.40, Decl. = +36o17'03".5 (equinox 2000.0; uncertainty
about 0".3), which is 2".8 west and 1".5 north of the core of the apparent
host galaxy (SDSS J025824.58+361701.9); a finding chart is posted at website
URL http://www.rotse.net/rsvp/j025824.58+361701.9/j025824.58+361701.9.jpg.
     A spectrogram, obtained on July 13.47 UT with the 9.2-m Hobby-Eberly
Telescope (+ Marcario Low-Resolution Spectrograph) by M. Shetrone, shows that
2013dz is a type-IIn supernova.  Correlation with a library of supernova
spectra using the "SuperNova IDentification" code (SNID; Blondin and Tonry
2007, Ap.J. 666, 1024) results in good spectral matches to various type-IIn
supernovae.  The spectrum is dominated by a relatively blue continuum and
moderately narrow (about 300-800 km/s) emission from H-alpha, H-beta, and
H-gamma at a redshift of z = 0.0490.  The H-alpha profile also shows evidence
of an underlying weaker, broad component (about 1800 km/s), and relatively
weak emission from the He I 587.6-nm line is also present.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2013 CBAT
2013 July 16                     (CBET 3589)              Daniel W. E. Green