[IAUC] CBET 3160: 20120703 : SUPERNOVA 2012de

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                                                  Electronic Telegram No. 3160
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 2012de
     [Editor's note:  this text replaces that on CBET 3159]
     V. Lipunov communicates the discovery by P. Podvorotniy, on behalf of the
MASTER team, of a possible supernova (mag 18.5) on three unfiltered CCD images
(limiting mag 19.2) obtained with the auto-detection system of the MASTER II
40-cm telescope (+ Apogee Alta U16m camera; field-of-view 2 x 4 square degrees)
at the Kislovodsk observatory (see website URL http://observ.pereplet.ru) on
June 25.952 UT.  The new object is located at R.A. = 22h15m05s.32, Decl. =
+10d18'12".6 (equinox 2000.0), which is 2".2 and 2".3 from the the centers
of two faint SDSS8 galaxies (magnitude r > 22.5) at position end figures
05s.40, 14".2 and 05s.40, 14".3.  Nothing is visible at this position on a
MASTER reference image from 2010 July 16 (limiting mag 18.0).  The discovery
and reference images are posted at the following website URL:
http://master.sai.msu.ru/static/OT/221505.31101812.5.png.

     J. M. Silverman, D. P. Cohen, and A. V. Filippenko, University of
California, Berkeley, report that inspection of a CCD spectrum (range 340-1000
nm), obtained on June 27.4 UT with the Shane 3-m reflector (+ Kast
spectrograph) at Lick Observatory, shows that 2012de is a type-Ia supernova.
Cross-correlation with a library of supernovae spectra using the "SuperNova
IDentification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) indicates
that 2012de is a normal type-Ia supernova near maximum brightness at a
redshift of 0.090.

     L. Tomasella, A. Pastorello, S. Valenti, S. Benetti, E. Cappellaro, M.
Turatto, and P. Ochner, Osservatorio Astronomico di Padova, Istituto Nazionale
di Astrofisica, report that a spectrogram of 2012de obtained on June 29.98 UT
with the Asiago 1.82-m Copernico Telescope (+ AFOSC; range 340-820 nm;
resolution 2.4 nm) indicates that this is a type-Ia supernova.  Cross-
correlation with a library of supernova spectra via the "Supernova
Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) shows
that 2012de is similar to several normal type-Ia supernovae a few days after
maximum at a redshift around z = 0.09.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2012 CBAT
2012 July 3                      (CBET 3160)              Daniel W. E. Green