[IAUC] CBET 3236: 20120923 : SUPERNOVAE 2012ez AND 2012fa

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                                                  Electronic Telegram No. 3236
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


SUPERNOVAE 2012ez AND 2012fa
     E. Cappellaro, S. Benetti, A. Pastorello, L. Tomasella, and M. Turatto,
Osservatorio Astronomico di Padova, Istituto Nazionale di Astrofisica (INAF);
G. Pignata and F. Bufano, Universidad Andres Bello; M. T. Botticella, A.
Grado, and L. Limatola, Osservatorio Astronomico di Capodimonte, INAF; M.
Vaccari, University of the Western Cape, South Africa; and M. Capaccioli, G.
Covone, and M. Paolillo, Universita Federico II, Napoli, on behalf of the
SUDARE/VOICE collaboration, report the discovery of the first two supernovae
on r-band images taken during their supernova search program with the European
Southern Observatory (ESO) VLT Survey Telescope (+ Omegacam).  The new objects
were discovered in the VOICE-CDFS-2 field, an extended area centered on the
Chandra Deep Field South.

 SN       2012 UT          R.A. (2000.0) Decl.      Mag.      Offset
 2012ez   Sep.  8.30    3 35 16.368  -27 29 49.21   23.2    1".1 E, 0".1 S
 2012fa   Sep. 14.24    3 34 59.022  -27 51 55.43   23.4       --

     A spectrogram of 2012ez, obtained on Sept. 14.28 UT with the ESO Very
Large Telescope Antu (+ FORS2; range 370-920 nm, resolution 10 nm), shows the
typical features of a normal type-Ia supernova.  Adopting a redshift z =
0.348, as measured from a number of narrow lines of the host galaxy, the best
fit with the GELATO tool (Harutyuyan et al. 2008, A.Ap. 488, 383) in a library
of supernova spectra is with SN 1995al at fourteen days past maximum (Anupama
et al. 1997, A.J. 114, 2054).  The ejecta expansion velocity, derived from the
position of the Si II doublet, is 11300 km/s.
     A spectrogram of 2012fa, which is located at the center of a very faint
galaxy, was obtained on Sept. 15.27 as above.  Cross-correlation with a
library of supernova spectra using the Supernova Identification tool (SNID;
Blondin and Tonry 2007, Ap.J. 666, 1024) shows that the object is very similar
to the bright type-Ia supernova 1991T at ten days before maximum (Ruiz-
Lapuente et al. 1992, Ap.J. 387, L33) when placed at a redshift, z, of about
0.4.  As for SN 1991T at this phase, the Si II doublet is barely visible.


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                         (C) Copyright 2012 CBAT
2012 September 23                (CBET 3236)              Daniel W. E. Green