[IAUC] CBET 2042: 20091124 : SUPERNOVA 2009kr IN NGC 1832

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                                                  Electronic Telegram No. 2042
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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SUPERNOVA 2009kr IN NGC 1832
     W. Li, A. V. Filippenko, and A. A. Miller, University of California,
Berkeley; J.-C. Cuillandre, Canada-France-Hawaii Telescope (CFHT) Corporation;
and N. Elias-Rosa and S. D. Van Dyk, Spitzer Science Center, California
Institute of Technology, report that they have isolated a probable progenitor
for the type-II supernova 2009kr (cf. CBETs 2006, 2011) in Hubble Space
Telescope (HST) images of NGC 1832 (GO program 10877) taken with the Wide
Field Planetary Camera 2 (WFPC2).  Geometrical transformation between a
combined 160-s r-band image taken with the 3.6-m CFHT's MegaCam on Nov. 21.49
UT and the HST/WFPC2 images yields a precision of 0.43 WFPC2 pixel (0".043)
for the supernova location on the WFPC2 images.  Within the uncertainty of
the supernova position, an object is clearly detected in the F555W and F814W
images, with a position of R.A. = 5h12m03s.247, Decl. = -15o41'53".10 (equinox
2000.0), an I magnitude of 23.6, and a color of V-I = +1.0.  Correcting the
photometry with the Milky Way reddening of E(B-V) = 0.073 mag (Schlegel et al.
1998, Ap.J. 500, 525), adopting a distance modulus to NGC 1832 of 32.0 mag,
and assuming no host-galaxy reddening, the object has an absolute I-band
magnitude of -8.5 and an intrinsic V-I color of 0.9 mag, consistent with a
star having 20-25 solar masses.  It is also possible that the identified
object is a compact star cluster, given its brightness.  More analysis is in
progress, and efforts will be made to further improve the astrometric
precision.  A finder chart for the possible progenitor is provided at
website URL http://astro.berkeley.edu/~weidong/sn2009kr-prog.gif.


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                         (C) Copyright 2009 CBAT
2009 November 24                 (CBET 2042)              Daniel W. E. Green