Electronic Telegram No. 3739
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 2013gv IN IC 1890 = PSN J03095731+1912492
     Seiichiro Kiyota, Kamagaya, Japan, reports the discovery by Kunihiro
Shima (Fuchu, Tokyo, Japan) of an apparent supernova (mag 17.2) on 29
unfiltered CCD frames taken on Dec. 4.705 UT with a 0.45-m f/12 reflector (+
FLI ML-8300 CCD camera) at Fujimi-machi, Nagano, Japan.  The new object is
located at R.A. = 3h09m57s.31, Decl. = +19d12'49".2 (equinox 2000.0), which
is 17" west and 20" north of the center of IC 1890.  Shima notes that nothing
is visible at this position on an image from the Digitized Sky Survey.  The
variable was designated PSN J03095731+1912492 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2013gv based on the
spectroscopic confirmation reported below.  Additional CCD magnitudes for
2013gv:  Dec. 5.403, 17.6 (Toshihide Noguchi, Katori, Chiba-ken, Japan;
eight stacked 30-s frames taken with a 0.23-m f/6.3 Schmidt-Cassegrain;
limiting mag 18.5; position end figures 57s.31, 48".9; offset 16" west, 20"
north; communicated by Syuichi Nakano, Sumoto, Japan; image posted at website
URL http://park8.wakwak.com/~ngc/images/PSNinIC1890.jpg); 5.431, V = 17.76,
I_c = 17.49 (Kiyota; remotely with an iTelescope 0.5-m astrograph + FLI
PL-9000 CCD camera at Siding Spring); 5.451, 17.9 (Koichi Itagaki, Teppo-cho,
Yamagata, Japan; position end figures 57s.30, 48".4; image posted at website
URL http://www.k-itagaki.jp/images/ic1890.jpg); 5.868, 17.5 (Gianluca Masi,
Francesca Nocentini, and Patrick Schmeer; remotely using a 43-cm telescope
near Ceccano, Italy; position end figures 57s.28, 48".1); 5.926, 18.3 (M.
Martignoni, Magnago, Italy; 0.25-m Schmidt-Cassegrain reflector; position end
figures 57s.31, 47".1; PPMXL reference stars); 7.943, 17.1 (F. Luppi, M.
Calabro, A. Medda, and A. Piovanelli, Varese, Italy; 0.38-m f/6.8 reflector;
position end figures 57s.28, 48".2; reference stars from CMC-14 catalogue;
image posted at URL http://www.astrogeo.va.it/pub/TOCP/PSN_I1890.jpg).

     I. Ueno, K. Kawaguchi, K. Takaki, and K. S. Kawabata, Hiroshima
University; and M. Yamanaka, Kyoto University, obtained a low-resolution
optical spectrogram (range 480-900 nm) of PSN J03095731+1912492 = SN 2013gv
on Dec. 7.5 UT with the 1.5-m Kanata telescope (+ HOWPol) at Higashi-Hiroshima
Observatory.  A comparison with a library of supernova spectra using GELATO
(Harutyunyan et al. 2008, A.Ap. 488, 383) suggests that the spectrum is
consistent with that of a type-Ia supernova a few days before maximum.  The
best match is with SN 1992A at five days before B-band maximum.  After
correction for the recession velocity of the host galaxy, the spectrum
exhibits an absorption line of Si II 635.5-nm at 609 nm, which corresponds to
a line velocity of -12000 km/s.

     P. Ochner, L. Tomasella, L. Tartaglia, A. Pastorello, S. Benetti, E.
Cappellaro, N. Elias-Rosa, and M. Turatto, Osservatorio Astronomico di Padova,
Istituto Nazionale di Astrofisica, report that an optical spectrogram (range
340-820 nm; resolution 1.3 nm) of PSN J03095731+1912492 = SN 2013gv, obtained
on Dec. 6.92 UT with the Asiago 1.82-m Copernico Telescope (+ AFOSC), shows it
to be normal type-Ia supernova.  Adopting for the host galaxy (IC 1890) a
recessional velocity of 10229 km/s (Giovanelli et al. 1993, A.J. 105, 1271;
via NED), a good match is found with several type-Ia supernovae at a few days
before B-band maximum.  An expansion velocity of about 12000 km/s is derived
from the minimum of the Si II 635-nm line.  The Asiago classification spectra
are posted at website URL http://sngroup.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 December 8                  (CBET 3739)              Daniel W. E. Green