[IAUC] CBET 3068: 20120325 : SUPERNOVA 2012bj = PSN J08433232+3200172

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                                                  Electronic Telegram No. 3068
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 2012bj = PSN J08433232+3200172
    K. Sarneczky, Konkoly Observatory; J. Vinko, University of Szeged; and
J. C. Wheeler, University of Texas, report the discovery of a supernova (mag
about 20) on a 22.5-min co-added unfiltered CCD image (limiting mag 21.5)
taken on Mar. 15.83 UT with the 0.60-m Schmidt telescope at Konkoly
Observatory at Piszkesteto, Hungary.  The new object is located at R.A. =
8h43m32s.32, Decl. = +32d00'17".2 (equinox 2000.0), which is about 1" west
and 1" north of the center of the presumed host galaxy, SDSS
J084332.35+320016.4 (whose r magnitude is 20.65).  The variable was designated
PSN J08433232+3200172 when it was posted at the Central Bureau's TOCP webpage
and is here designated SN 2012bj based on the spectroscopic confirmation
reported below.  Additional CCD magnitudes for 2012bj:  2011 Mar. 24, [22
(Sarneczky et al.; co-added 37.5-min reference image); 2012 Mar. 22.79, R =
20.7 +/- 0.5 (Sarneczky, T. Szalai, A. Szing, and J. Vinko; 1-m RCC telescope
at Piszkesteto); 23.286, 20.6 (Joseph Brimacombe, Cairns, Australia; remotely
using a 51-cm RCOS telescope + STL11K camera + luminance filter at the New
Mexico Skies Observatory near Mayhill, NM, U.S.A.; position end figures
32s.32, 16".4).  Brimacombe has posted his image at the following website URL:
http://www.flickr.com/photos/43846774@N02/7010386957/.
     Sarneczky et al. add that a spectrogram obtained on Mar. 23.25 UT with
the 9.2-m Hobby-Eberly Telescope (+ Marcario Low-Resolution Spectrograph) by
S. Rostopchin shows that PSN J08433232+3200172 = 2012bj is a peculiar type-Ia
supernova a few days before maximum.  According to SNID (Blondin and Tonry
2007, Ap.J. 666, 1024), the spectrum most resembles that of SN 2000cx at -4
days relative to B-band maximum light.  The most prominent broad features are
Fe III 440.4-nm and 512.9-nm, while the Si II 635.5-nm feature is weak.  The
median redshift estimate is z = 0.167.  Adopting this redshift, the magnitude
estimate above corresponds to absolute magnitude -18.5, which is consistent
with the pre-maximum light curve of a supernova-2000cx-like event.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
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                         (C) Copyright 2012 CBAT
2012 March 25                    (CBET 3068)              Daniel W. E. Green