Electronic Telegram No. 3158
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@eps.harvard.edu (alternate cbat@iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


SUPERNOVA 2012dd IN PGC 32926 = PSN J10571646+2832217
     E. Briggs, J. Newton, and T. Puckett report the discovery of an apparent
supernova (mag 17.6) on unfiltered CCD images (limiting mag 19.0) taken with a
0.35-m reflector at Portal, AZ, U.S.A., on June 5.189 UT in the course of the
Puckett Observatory Supernova Search.  The new object, is located at R.A. =
10h57m16s.46, Decl. = +28o32'21".7 (equinox 2000.0), which is 3".6 west and
8".9 south of the center of PGC 32926.  Puckett has posted an image of the
variable at website URL http://www.possdata.com/PSNJ10571646+2832217.jpg.
The variable was designated PSN J10571646+2832217 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2012dd based on the
spectroscopic confirmation reported below.  Additional magnitudes for 2012dd:
Apr. 19, [19.1 (Puckett); June 6.175, 17.4 (Puckett; 0.35-m reflector at
Portal; limiting mag 19.1); 7.214, 16.3 (L. Elenin, Lyubertsy, Russia, and I.
Molotov, Moscow; remotely taken at the ISON-NM Observatory near Mayhill, NM,
USA, with a 0.45-m f/2.8 telescope; position end figures 16s.42 +/- 0".15,
21".3 +/- 0".15; NOMAD reference stars; limiting mag about 20.0; image posted
at URL http://spaceobs.org/images/TOCP/PSNJ10571646+2832217-20120607.png);
7.409, R = 17.2 (Joseph Brimacombe, Cairns, Australia; 33-cm RCOS telescope +
STL6K camera; position end figures 16s.37, 21".3; image posted at website URL
http://www.flickr.com/photos/43846774@N02/7162934149/); 9.401, R = 16.9
(Brimacombe; position end figures 16s.44, 21".3; image posted at website URL
http://www.flickr.com/photos/43846774@N02/7173174687/).

     S. Benetti, L. Tomasella, S. Valenti, A. Pastorello, E. Cappellaro, M.
Turatto, and P. Ochner, Osservatorio Astronomico di Padova, Istituto Nazionale
di Astrofisica, report that a spectrogram of PSN J10571646+2832217 = 2012dd,
obtained on June 29.86 UT with the Asiago 1.82-m Copernico Telescope (+ AFOSC;
range 340-820 nm; resolution 2.4 nm), suggests that it is a normal type-Ia
supernova.  Adopting for the host galaxy (PGC 32926) a redshift z = 0.045739
(SDSS 2007, via NED), the comparison with a library of supernovae spectra via
GELATO (Harutyuyan et al. 2008, A.Ap. 488, 383) shows that 2012dd is an event
similar to the type-Ia supernova 1994D (Patat et al. 1996, MNRAS 278, 111) at
ten days after maximum.


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

                         (C) Copyright 2012 CBAT
2012 July 1                      (CBET 3158)              Daniel W. E. Green