[IAUC] CBET 3334: 20121207 : SUPERNOVA 2012hk = PSN J10411534+3733218

Jue Dic 6 21:26:18 ART 2012

                                                  Electronic Telegram No. 3334
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 2012hk = PSN J10411534+3733218
     V. Lipunov, Sternberg Astronomical Institute (SAI), reports the discovery
by P. Balanutsa of a possible supernova (mag 16.7) on two unfiltered images
(limiting mag 18.3) taken on Nov. 20.742 and 20.774 UT with the MASTER-Amur
robotic telescope (0.40-m f/2.5 reflector).  The new object is located at R.A.
= 10h41m15s.34, Decl. = +37d33'21".8 (equinox 2000.0), which is 17".7 west and
25".2 north of a nearby galaxy (PGC 2103473).  D. Denisenko and E. Gorbovskoy
(SAI) report that nothing is visible at this position on a MASTER-Amur survey
image from Oct. 28.879 (limiting mag 18.4), or on fifteen digitized Palomar
Observatory Sky Survey plates (to limiting mag about 21) or on a Sloan Digital
Sky Survey color image (to limiting mag about 23).  The discovery and
reference images are posted at the following website URL:
http://master.sai.msu.ru/static/OT/104115.34373321.8.png.  The variable was
designated PSN J10411534+3733218 when it was posted at the Central Bureau's
TOCP webpage and is here designated SN 2012hk based on the spectroscopic
confirmation reported below.  Three 300-s images (limiting mag about 19.3)
obtained remotely with a 0.45-m f/2.8 telescope at the ISON-NM Observatory
near Mayhill, NM, USA, on Nov. 27.396 by L. Elenin (Lyubertsy, Russia) and I.
Molotov (Moscow, Russia) yield position end figures 15s.45 +/- 0".13, 23".3
+/- 0".11 (UCAC-4 reference stars) and unfiltered mag 17.8; their image is
posted at http://spaceobs.org/images/TOCP/PSNJ10411534+3733218-20121127.png.

     L. Tomasella, S. Benetti, E. Cappellaro, P. Ochner, A. Pastorello and M.
Turatto, Osservatorio Astronomico di Padova, Istituto Nazionale di Astrofisica,
report that optical spectroscopy (range 340-820 nm; resolution 1.3 nm),
obtained on Dec. 5.19 UT with the Asiago 1.82-m Copernico Telescope (+ AFOSC;
range 350-820 nm; resolution 1.3 nm), shows that PSN J10411534+3733218 = SN
2012hk is a type-II supernova at redshift z = 0.023986 (Sloan Digital Sky
Survey Data Release 5, 2006; via NED database) or a supernova impostor.  The
low-signal-to-noise spectrum shows narrow H_alpha in emission (with a FWHM
velocity of about 700 km/s, close to the spectral resolution limit),
superimposed on a broader component (with FWHM velocity of 2800 km/s).  This
line profile of H_alpha is consistent with those observed in type-IIn
supernovae.  The Asiago classification spectra are posted at website URL
http://graspa.oapd.inaf.it; classification was made via GELATO (Harutyunyan
et al. 2008, A.Ap. 488, 383) and SNID (Blondin and Tonry 2007, Ap.J. 666,
1024).


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

                         (C) Copyright 2012 CBAT
2012 December 7                  (CBET 3334)              Daniel W. E. Green