[IAUC] CBET 3014: 20120206 : SUPERNOVA 2012Z IN NGC 1309 = PSN J03220535-1523156

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                                                  Electronic Telegram No. 3014
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 2012Z IN NGC 1309 = PSN J03220535-1523156
     Further to CBET 2929, S. B. Cenko, W. Li, and A. V. Filippenko report the
LOSS discovery of an apparent supernova on unfiltered KAIT images:

 SN       2012 UT       R.A. (2000.0) Decl.      Mag.      Offset
 2012Z    Jan. 29.15   3 22 05.35  -15 23 15.6   17.6    14".6 W, 43".1 N

The variable was designated PSN J03220535-1523156 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2012Z based on the
spectroscopic confirmation reported below.  Additional CCD magnitudes for
2012Z:  Jan. 26.17 UT, [18.6 (KAIT); 31.164, R = 15.6 +/- 0.2 (J. Brimacombe,
Cairns, Australia; remotely using a 51-cm RCOS telescope + STL11K camera + red
filter at the New Mexico Skies Observatory near Mayhill, NM, U.S.A.; position
end figures 05s.39, 15".2).  Brimacombe's image is posted at the following
website URL:  http://www.flickr.com/photos/43846774@N02/6798382185/.

     Samuel Meyer, Harvard University; Kimberly Emig, University of Hawaii at
Hilo; and Catherine Kaleida and Eric E. Mamajek, Cerro Tololo Inter-American
Observatory, report on preliminary BVRI photometry of PSN J03220535-1523156 =
SN 2012Z, taken with the SMARTS 1.0-m telescope (+ Y4K camera) at Cerro Tololo
in non-photometric conditions (light cloud), using relative photometry
(uncertainty +/- 0.1 mag) via the neighboring photometric standard star 2MASS
J03220561-1522352 = UCAC3 150-008318, with Landolt BVRI photometry taken from
Ganeshalingam et al. (2010, Ap.J. Suppl. 190, 418):  Jan. 31.1289 UT, R =
16.6; 31.1315, R = 16.6; 31.1343, V = 16.4; 31.1383, B = 16.2; 31.1417, I =
16.2; 31.1467, I = 16.2; 31.1500, B = 16.2; 31.1535, V = 16.2.

     S. B. Cenko, D. P. Cohen, A. V. Filippenko, J. M. Silverman, and M.
Ganeshalingam, University of California, Berkeley, report that inspection of a
CCD spectrum (range 340-1000 nm), obtained on Feb. 1 UT with the 3-m Shane
reflector (+ Kast) at Lick Observatory, shows that 2012Z is a peculiar type-Ia
supernova about a week before maximum light.  Cross-correlation with a library
of supernova spectra using the "Supernova Identification" code (SNID; Blondin
and Tonry 2007, Ap.J. 666, 1024) reveals that the spectrum of 2012Z is similar
to those of SN 2005hk (Chornock et al. 2006, PASP 118, 722) and SN 1991T
(Filippenko et al. 1992, Ap.J. 384, L15) at around this epoch.  The continuum
emission is quite blue, with a weak Si II 635.5-nm feature.  The object should
become relatively bright; further follow-up observations are encouraged.


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

                         (C) Copyright 2012 CBAT
2012 February 6                  (CBET 3014)              Daniel W. E. Green