[IAUC] CBET 3120: 20120523 : SUPERNOVA 2012cj IN NGC 5156 = PSN J13284343-4854356

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                                                  Electronic Telegram No. 3120
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 2012cj IN NGC 5156 = PSN J13284343-4854356
     Colin Drescher, Calamvale, Queensland, Australia, reports the discovery
of an apparent supernova (red mag 17.6) on unfiltered CCD images taken on May
18.479 and 19.307 UT by Stuart Parker (Oxford, Canterbury, New Zealand) with a
35-cm Celestron C14 reflector (+ ST10 CCD camera).  The new object is located
at R.A. = 13h28m43s.43, Decl. = -48d54'35".6 (equinox 2000.0; magnitude and
position measured by Drescher), which is 7" west and 25" north of the nucleus
of the galaxy NGC 5156.  Nothing is visible at this position on an image taken
by Parker on May 3.594 (limiting red mag 18.8).  The variable was designated
PSN J13284343-4854356 when it was posted at the Central Bureau's TOCP webpage
and is here designated SN 2012cj based on the spectroscopic confirmation
reported below.

     J. T. Parrent and D. A. Howell report that a CCD spectrum (range 350-900
nm) of PSN J13284343-4854356 = 2012cj was taken with the Gemini South
telescope on May 20 UT.  The spectrum reveals Balmer-series P-Cyg profiles,
and the minimum of the H-alpha absorption feature is blue-shifted by about
10500 km/s (assuming a host-galaxy redshift of z = 0.01 for NGC 5156).
Comparisons to other spectra with "Superfit" (Howell et al. 2005, Ap.J. 634,
1190) show similar overlap with the type-IIP supernova 1999em near maximum
light.


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                         (C) Copyright 2012 CBAT
2012 May 23                      (CBET 3120)              Daniel W. E. Green