Electronic Telegram No. 3585
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 2013dw = PSN J16135884+4241590
     Li Zhou and Xiaofeng Wang, Tsinghua University (THU), China; and Tianmeng
Zhang, National Astronomical Observatories of China (NAOC), report the
discovery of an apparent supernova (mag 18.8) on unfiltered CCD images taken
on July 2.60 UT using the 0.6-m NAOC Schmidt telescope in the course of the
THU-NAOC Transient Survey (TNTS).  The new object is located at R.A. =
16h13m58s.84, Decl. = +42d41'59".0 (equinox 2000.0), which is 1".7 east and
0".1 north of the center of the galaxy SDSS J161358.73+424158.9.  Nothing is
visible at this position on archival images obtained on Mar. 24 (limiting mag
about 20.0).  The TNTS images are posted at the following website URL:
http://www.thca.tsinghua.edu.cn/~wangxf/TNTS/PSNJ16135884+4241590.png.  The
variable was designated PSN J16135884+4241590 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2013dw based on the
spectroscopic confirmation reported below.

     Jun Mo and Xiaofeng Wang, Tsinghua University; and Tianmeng Zhang,
National Astronomical Observatories of China (NAOC), report on an optical
spectrogram (range 450-850 nm) that was obtained on July 5.60 UT with the
2.16-m telescope (+ OMR) at the Xinglong Station of the NAOC.  The spectrum
of 2013dw is consistent with a type-IIn supernova at about one month after
maximum light.  Cross-correlation with a library of supernova spectra using
the "Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666,
1024) shows that 2013dw matches with SN 2010jl at +30 days.  From the narrow
emission lines of the spectrum, they measure a redshift of 0.136 for the host
galaxy, SDSS J161358.73+424158.9.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2013 CBAT
2013 July 14                     (CBET 3585)              Daniel W. E. Green