Electronic Telegram No. 3427
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 2013af = PSN J09135517+5546567
     Li Zhou, Xiaofeng Wang, and Juncheng Chen, Tsinghua University (THU);
and Tianmeng Zhang and Xu Zhou, National Astronomical Observatories of China
(NAOC), report the discovery of an apparent supernova (mag 18.9) on unfiltered
CCD images taken on Mar. 1.50 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. = 9h13m55s.17, Decl. = +55d46'56".7 (equinox 2000.0), which is 15" east
and 2" south of the center of the galaxy SDSS J091355.23+554652.2.  Nothing is
visible at this position on archival images obtained on 2012 Dec. 15 (limiting
mag about 20.0) or on a Digitized Sky Survey image from the Palomar Sky
Survey.  The TNTS discovery images have been posted at the following website
URL:  http://www.thca.tsinghua.edu.cn/~wangxf/TNTS/PSNJ09135517+5546567.png.
The variable was designated PSN J09135517+5546567 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2013af based on the
spectroscopic confirmation reported below.  Additional CCD magnitudes for
2013af:  2012 Dec. 15, [20.0 (TNTS); 2013 Feb. 15, 19.2 (TNTS); Mar. 3.320,
19.0 (Joseph Brimacombe, Cairns, Australia; remotely using a 51-cm RCOS
telescope + luminance filter at the New Mexico Skies observatory near Mayhill,
NM, U.S.A.; position end figures 55s.17, 56".6; image posted at website URL
http://www.flickr.com/photos/43846774@N02/8526776647/).

     Jujia Zhang, Yunnan Astronimical Observatory (YNAO); Xulin Zhao and
Xiaofeng Wang, Tsinghua University; and Tianmeng Zhang, National Astronomical
Observatories of China, report on an optical spectrogram (range 350-880 nm)
of PSN J09135517+5546567 = SN 2013af that was obtained on Mar. 2.58 UT with
the 2.4-m telescope (+ YFOSC) at the LiJiang Gaomeigu Station of the YNAO.
The spectrum is consistent with a type-II-P supernova a few days 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 2013af matches with SN 2004dj at +17 days.  Adopting a
redshift of 0.035 from the SNID fit for the presumed host galaxy, the
absorption minimum of the H-alpha line is found to be blueshifted by about
7400 km/s.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2013 CBAT
2013 March 4                     (CBET 3427)              Daniel W. E. Green