[IAUC] CBET 3149: 20120620 : SUPERNOVA 2012cx IN PGC 59729 = PSN J17100586+4222235

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                                                  Electronic Telegram No. 3149
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 2012cx IN PGC 59729 = PSN J17100586+4222235
     E. Sanders, R. Kot, and D. Coffin report the discovery of an apparent
supernova (mag 17.3) on a 180-s unfiltered CCD image taken with the 0.37-m
f/14 Rigel telescope at the Iowa Robotic Observatory near Sonoita, Arizona, on
June 15.29 UT.  The new object is located at R.A. = 17h10m05s.861, Decl. =
+42o22'23".47 (equinox 2000.0), which is 10".7 east and 5".1 north of the
nucleus of PGC 59729 (whose position end figures are 05s.150, 18".38).  A Rigel
image taken on June 9.31 showed nothing at this position (limiting mag about
19), while a 240-s unfiltered Rigel image taken on June 16.26 confirmed the
variable at mag 17.3.  PGC 59729 = MCG +07-35-37 was host to the type-IIP
supernova 2011bi (cf. CBET 2691; position end figures 05s.81, 20".1).  The
variable was designated PSN J17100586+4222235 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2012cx based on the
spectroscopic confirmation reported below.  J. Brimacombe, Cairns, Australia,
obtained a CCD image with a 41-cm RCOS telescope (+ STL6K camera + infrared
filter; bandpass > 700 nm) on June 17.597, yielding mag 17.5 and position end
figures 05s.83, 22".5; his image is posted at the folloing website URL:
http://www.flickr.com/photos/43846774@N02/7391545030/.

     G. H. Marion, Harvard-Smithsonian Center for Astrophysics (CfA), on
behalf of the CfA Supernova Group, reports that a spectrogram (range 340-740
nm) of PSN J17100586+4222235 = 2012cx was obtained on June 19 UT by L. Macri
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 2012cx is a type-Ia supernova a few days before maximum light.  A good
fit is found to the template of SN 2007A at 3 days before maximum.  The
velocity of the Si II 635.5-nm absorption feature is measured to be
approximately 11400 km/s, using a redshift of z = 0.027672 for PGC 59729
(from Marzke et al. 1996, A.J. 112, 1803; via NED).


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2012 CBAT
2012 June 20                     (CBET 3149)              Daniel W. E. Green