Electronic Telegram No. 3660
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 2013fl IN UGC 10908 = PSN J17333955+5022255
     T. Boles, Coddenham, England, reports the discovery of an apparent
supernova (mag 17.6) on unfiltered CCD images taken on Sept. 22.882 UT with a
0.35-m reflector.  The new object is located at R.A. = 17h33m39.53s. Decl. =
+50o22'25".5, which is approximately 16".7 east and 1".2 north of the center
of UGC 10908. Nothing is present at this position on Digitized Sky Survey
plates from 1987 Apr. 24 (limiting red mag 20.5), and 1987 May 4 (limiting
blue mag 21.0).  The variable was designated PSN J17333955+5022255 when it was
posted at the Central Bureau's TOCP webpage and is here designated SN 2013fl
based on the spectroscopic confirmation reported below.  Additional CCD
magnitudes for 2013fl:  2013 May 2, [19.5 (Boles); June 6, [19.5 (Boles);
Sept. 23.798, 17.5 (Ron Arbour, South Wonston, U.K.; 35-cm f/6 reflector;
position end figures 39s.57, 25".8); Sept. 23.81, 17.0 (Nick James, Chelmsford,
Essex, England; Celestron C11 reflector + ST9XE camera; position end figures
39s.54,25".4; UCAC-3 reference stars); Sept. 23.853, 17.4 (Federica Luppi and
Luca Buzzi, Varese, Italy, 0.36-m f/7.1 reflector; position end figures 39s.54,
25".6; they note that a knot or H II region is visible in DSS images at
position end figures 39s.67, 23".4; their image is posted at website URL
http://www.astrogeo.va.it/pub/TOCP/PSN_U10908.jpg); Sept. 25.895, 16.7 (Denis
Buczynski, Portmahomack, U.K.; Celestron C14 telescope; position end figures
39s.52, 25".5; UCAC reference stars).

     Tianmeng Zhang, National Astronomical Observatories of China (NAOC); and
Xiaofeng Wang, Tsinghua University, report on an optical spectrogram (range
390-870 nm) of PSN J17333955+5022255 = SN 2013fl that was obtained on Sept.
25.48 2013 UT with the 2.16-m telescope (+ OMR) at the Xinglong Station of the
NAOC.  The spectrum is consistent with that of 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 2013fl matches with SN 1999em at +5 days.
Adopting a redshift of 0.0194 for the host galaxy, UGC 10908 (Springob
et al. 2005, Ap.J. Suppl. 160, 149), they measure an H-alpha P-Cyg
absorption minimum velocity of about 9300 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 September 30                (CBET 3660)              Daniel W. E. Green