Electronic Telegram No. 1306
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
CBAT@CFA.HARVARD.EDU (science)
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SUPERNOVA 2008ax IN NGC 4490
     W. Li and A. V. Filippenko, University of California, Berkeley; and
S. D. Van Dyk, Spitzer Science Center, California Institute of Technology,
on behalf of a larger team, report on their analysis of the available
HST/WFPC2 images of the field of SN 2008ax in NGC 4490, and derive the
following additional photometric magnitudes for the possible progenitor star
of 2008ax (cf. CBETs 1290, 1298):  [F450W] = 23.55 +/- 0.09, [F606W] = 23.64
+/- 0.13, [F814W] = 22.58 +/- 0.08.  These magnitudes and colors are not
consistent with a single star having significant reddening [E(B-V) = 0.5 mag,
as reported on CBET 1298], suggesting that the site of 2008ax is contaminated
by several sources.  A plausible scenario is that there are two stars near
the supernova site:  one is the reddened progenitor of SN 2008ax, while the
other is a blue supergiant suffering little extinction (thus unlikely to be
related to SN 2008ax).  Further analysis is ongoing.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2008 CBAT
2008 March 19                    (CBET 1306)              Daniel W. E. Green