Electronic Telegram No. 2213
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
CBAT Director:  Daniel W. E. Green; Room 209; Dept. of Earth and Planetary
 Sciences; Harvard University; 20 Oxford St.; Cambridge, MA  02138; U.S.A.
e-mail:  cbat@iau.org; cbatiau@eps.harvard.edu
URL http://www.cfa.harvard.edu/iau/cbat.html


POSSIBLE SUPERNOVA IN IC 883:  PSN K1002-1
     E. Kankare and S. Mattila, Tuorla Observatory; S. Ryder, Anglo-Australian
Observatory; M. A. Perez-Torres, C. Romero-Canizales, and A. Alberdi,
Instituto de Astrofisica de Andalucia, CSIC; A. Alonso-Herrero and L. Colina,
Instituto de Estructura de la Materia, CSIC; A. Efstathiou, European
University of Cyprus; J. Kotilainen, Finnish Centre for Astronomy, European
Southern Observatory; and P. Vaisanen and Zara Randriamanakoto, South African
Astronomical Observatory, report the discovery of an apparent supernova on
near-infrared images of the luminous infrared galaxy IC 883 in the course of
their infrared search program (cf. CBETs 1392, 1569, 2145).  The new object,
designated PSN K1002-1, was detected at a K-band magnitude of about 17.7 in
eleven images (spatial resolution FWHM about 0".1) obtained using NIRI and the
ALTAIR laser-guide-star adaptive-optics system on the Gemini-North Telescope
on 2010 Feb. 24.6 UT, via comparison with images obtained with the same
instrument on 2009 June 10.4.  The new object is located 0".24 east and 0".29
south of the galaxy's K-band nucleus, at R.A = 13h20m35s.36, Decl. =
+34o08'22".2 (equinox 2000.0).  Adopting a distance of 100 Mpc for IC 883 (z
= 0.023299; Rothberg and Joseph 2006, A.J. 131, 185; and H_o = 70 km/s/Mpc),
this corresponds to a projected distance of about 180 pc, which would make
this the closest supernova discovered yet in a luminous infrared galaxy
nucleus at infrared wavelengths.  High spatial resolution follow-up
observations at infrared and radio wavelengths are encouraged.  The new
source is measured to remain stationary with a precision of 0".02 in the
eleven 30-s Gemini exposures (spatial resolution FWHM about 0".1), with the
first and the last one separated by about 6 minutes.  A variable foreground
star also provides a very improbable alternative explanation, given the small
field-of-view (22".5 x 22".5) of the Gemini frames and the fact no transient
source has been detected in this galaxy in the authors' previous five epochs
of Gemini imaging over a period of 22 months.  Based on these arguments and
the fact that large numbers of core-collapse supernovae are expected in the
central few-hundred-parsec regions of luminous infrared galaxies as a result
of the large star-formation rates therein, they conclude that explanations
other than a supernova for this object are extremely unlikely.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
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                         (C) Copyright 2010 CBAT
2010 March 20                    (CBET 2213)              Daniel W. E. Green