[IAUC] CBET 2845: 20111001 : SUPERNOVA 2011gk IN UGC 1523 = PSN J02021902+1939396

Vie Sep 30 20:55:32 ART 2011

                                                  Electronic Telegram No. 2845
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 en eps.harvard.edu (alternate cbat en iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


SUPERNOVA 2011gk IN UGC 1523 = PSN J02021902+1939396
     B. Moore, A. Sehgal, and T. Puckett report the discovery of an apparent
supernova (mag 18.0) on an unfiltered CCD image (limiting mag 19.9) taken with
a 0.50-m reflector at Osoyoos, British Columbia, on Sept. 6.4795 UT in the
course of the Puckett Observatory Supernova Search.  The new object, which was
confirmed  at mag 18.0 on Sept. 7.439 by Sehgal at Osoyoos, is located at R.A.
= 2h02m19s.02, Decl. = +19o39'39".6 (equinox 2000.0), which is 2".8 west and
8".5 north of the center of UGC 1523.  Nothing is visible at this position on
images taken by Puckett on 2010 Oct. 17 (limiting mag 19.8).  Puckett has
posted an image at website URL http://possdata.com/PSNJ02021902+1939396.jpg.
The variable was designated PSN J02021902+1939396 when it was posted on the
Central Bureau's TOCP webpage and is here designated SN 2011gk based on the
spectroscopic confirmation reported below.  Joseph Brimacombe, Cairns,
Australia, reports mag 19.1 and position end figures 19s.01, 38".9 from
stacked CCD images taken on Sept. 8.651 with an infrared filter; his image is
posted at website URL http://www.flickr.com/photos/43846774@N02/6127931491/.

     G. H. Marion, Harvard-Smithsonian Center for Astrophysics (CfA), on behalf
of the CfA Supernova Group, reports that a spectrum (range 340-740 nm) of PSN
J02021902+1939396 = SN 2011gk was obtained on Sept. 29 UT by Marion with the
F. L. Whipple Observatory 1.5-m telescope (+ FAST).  Cross-correlation with a
library of supernova spectra using the "Supernova Identification" code (SNID;
Blondin and Tonry 2007, Ap.J. 666, 1024) shows that 2011gk is a type-Ia
supernova about one month after maximum light.  The best-fit SNID template is
to SN 2004L at +28 days and z = 0.043.

     S. Valenti, F. Bufano, S. Benetti, L. Tomasella, and P. Ochner,
Osservatorio Astronomico di Padova, Istituto Nazionale di Astrofisica; and
A. Pastorello, Dipartimento di Astronomia, Universita di Padova, on behalf of
a larger collaboration, report that a spectrogram (range 360-810 nm;
resolution 2.2 nm) of PSN J02021902+1939396 = SN 2011gk, obtained by the
Service Telescope Operator Team on Sept. 29.89 UT with the Ekar-Copernico
1.82-m telescope (+ AFOSC), is that of a type-Ia supernova.  Cross-correlation
with a library of supernova spectra via the "GELATO" code (Harutyunyan et
al. 2008, A.Ap. 488, 383; available at URL https://gelato.tng.iac.es/login.cgi),
suggest a normal type-Ia supernova about one month after the B-band maximum at
a redshift of z = 0.044 (Giovanelli and Haynes 1993, A.J. 105, 1271; via the
NED website).


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

                         (C) Copyright 2011 CBAT
2011 October 1                   (CBET 2845)              Daniel W. E. Green