[IAUC] CBET 3196: 20120802 : SUPERNOVA 2012dx IN PGC 63016 = PSN J19171735+3325487

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                                                  Electronic Telegram No. 3196
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 2012dx IN PGC 63016 = PSN J19171735+3325487
     F. Ciabattari, E. Mazzoni, and S. Donati, Borgo a Mozzano, Italy, report
their discovery of an apparent supernova (mag 16.9) on unfiltered CCD images
(limiting magnitude 19.5) obtained on July 26.95 and 27.83 UT with a 0.5-m
Newtonian telescope in the course of the Italian Supernovae Search Project.
The new object is located at R.A. = 19h17m17s.35, Decl. = +33d25'48".7
(equinox 2000.0; astrometry with respect to UCAC-2 stars), which is 2" east
and 15" north of the center of the galaxy PGC 63016.  The variable was
designated PSN J19171735+3325487 when it was posted at the Central Bureau's
TOCP webpage and is here designated SN 2012dx based on the spectroscopic
confirmation reported below.  Additional magnitudes for 2012dx:  1989 July 1,
[20.3 (Palomar Sky Survey, J plate; via Ciabattari); 1992 June 8, [20.3
(Palomar Sky Survey, F plate; via Ciabattari); 2012 July 8, [19.5 Ciabattari);
July 28.508, 17.3 (Joseph Brimacombe, Cairns, Australia; infrared filter;
position end figures 17s.33, 48".1; image posted at the following website URL:
http://www.flickr.com/photos/43846774@N02/7697140110/); July 29.314, 17.2
(Brimacombe; 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 17s.32, 48".1; image posted at the following website URL:
http://www.flickr.com/photos/43846774@N02/7674570352/).

     L. Tomasella, S. Benetti, A. Pastorello, P. Ochner, M. Turatto, S.
Valenti, and E. Cappellaro, Osservatorio Astronomico di Padova, Istituto
Nazionale di Astrofisica, report that a low-signal-to-noise spectrogram
of PSN J19171735+3325487 = 2012dx, obtained on July 30.96 UT with the Asiago
1.82-m Copernico Telescope (+ AFOSC; range 340-820 nm; resolution 2.4 nm),
suggests that this is a type-Ib supernova.  Together with prominent He I lines
with P-Cyg profiles, Fe II features are clearly detected.  Adopting for the
host galaxy (PGC 63016) a redshift z = 0.014934 (Strauss et al. 1992, Ap.J.
Suppl. 83, 29; via NED), a comparison with a library of supernovae spectra
via GELATO (Harutyuyan et al. 2008, A.Ap. 488, 383) shows that 2012dx is a
type-Ib event similar to SN 1983N (Richtler and Sadler 1983, A.Ap. 128, L3)
and SN 1999dn (Benetti et al. 2011, MNRAS 411, 2726) a few days after maximum
light.


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

                         (C) Copyright 2012 CBAT
2012 August 2                    (CBET 3196)              Daniel W. E. Green