Electronic Telegram No. 3305
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 2012go = PSN J22415183+3458074
     Ron Arbour, South Wonston, Hants, U.K., reports the discovery of an
apparent supernova (mag 17.0) on unfiltered CCD images taken on Nov. 14.955 UT
using a 35-cm f/6 Schmidt-Cassegrain telescope (+ SXVF-H9 camera) in the
course of his supernova patrol.  The new object is located at R.A. =
22h41m51s.83, Decl. = +34d58'07".4 (equinox 2000.0), which is 3" east and 4"
north of the center of the galaxy PGC 214858.  Nothing is visible at this
position on a Digitized Sky Survey Palomar blue plate from 1989 Sept. 8 or
a red plate from 1988 July 11 (no limiting magnitudes provided).  The variable
was designated PSN J22415183+3458074 when it was posted at the Central
Bureau's TOCP webpage and is here designated SN 2012go based on the
spectroscopic confirmation reported below.  Additional unfiltered CCD
magnitudes for 2012go:  2012 Nov. 16.048, 16.7 (R. A. Koff, Bennett, CO, USA;
Meade 0.25-m f/10 reflector + Apogee U-47 camera; limiting magnitude 20.0;
position end figures 51s.81, 06".8; UCAC3 reference stars; image posted at URL
http://antelopehillsobservatory.org/SNpictures/PSNJ22415183+3458074final.jpg);
17.850, 16.5 (D. Grennan, Dublin, Ireland; 0.36-m reflector + SBIG ST8 camera;
limiting mag 20.1; position end figures 51s.79, 06".7; image posted at URL
http://www.webtreatz.com/images/J22415183+3458074.jpg).

     E. Kankare, R. Rekola, and S. Mattila, University of Turku, report that a
spectrum of PSN J22415183+3458074 = SN 2012go was obtained (as a part of a NOT
Science school) on Nov. 19.0 UT with the Nordic Optical Telescope (+ ALFOSC;
range 320-910 nm, resolution 1.6 nm).  Cross-correlation with a library of
supernova spectra using the "GELATO" code (Harutyunyan et al. 2008, A.Ap. 488,
383; available at https://gelato.tng.iac.es/login.cgi) and "Supernova
Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) suggests
that SN 2012go is a normal type-Ia supernova at a redshift of about 0.03.  The
best matches were found with the spectra of SN 2002bo at a few days before
maximum light.

     R. Kotak, T.-W. Chen, and M. Fraser, Queen's University, Belfast, report
that a spectrum (range 330-975 nm; resolution about 1000) of PSN
J22415183+3458074 = SN 2012go was obtained on Nov. 20.81 UT with the 4.2-m
William Herschel Telescope (+ ISIS).  Cross-correlation with a library of
supernova spectra via the "Supernova Identification" code (SNID; Blondin and
Tonry 2007, Ap.J. 666, 1024) shows that SN 2012go is a young type-Ia supernova
(with a best match to SN 2002dj) at phase of between -7 and -3 days from
maximum light, and with a redshift of z = 0.03.  The redshift measured from
2012go is in agreement with that measured from narrow emission lines from the
host galaxy.


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

                         (C) Copyright 2012 CBAT
2012 November 24                 (CBET 3305)              Daniel W. E. Green