[IAUC] CBET 1299: 20080312 : SUPERNOVA 2008ax IN NGC 4490

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                                                  Electronic Telegram No. 1299
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 2008ax IN NGC 4490
     C. J. Stockdale, Marquette University and University of Oklahoma; K. W.
Weiler, Naval Research Laboratory; S. Immler, Goddard Space Flight Center;
S. D. Van Dyk, Spitzer Science Center, California Institute of Technology;
N. Panagia, Space Telescope Science Institute and Observatory of Catania; J.
M. Marcaide, University of Valencia; D. Pooley, University of Wisconsin at
Madison; and R. A. Sramek, National Radio Astronomy Observatory, report the
detection of radio emission near the position of the type-IIP supernova
2008ax (cf. CBET 1280) with the Very Large Array radio telescope.  A flux
density of 1.19 +/- 0.07 mJy was measured at 8.46 GHz (wavelength 3.5 cm)
and 5.80 +/- 0.59 mJy at 22.46 GHz (wavelength 1.3 cm) on Mar. 7.54 UT.  The
measured position of the radio emission of R.A. = 12h30m40.s80, Decl. =
+41o38'14".9 (equinox 2000.0) is in good agreement with the measured
optical position (end figures 40s.84, 15".4) given on CBET 1286.  Re-
observation on Mar. 10.25 indicates that the flux density of the radio source
has risen to 3.94 +/- 0.23 mJy at 8.46 GHz and 6.74 +/- 0.70 mJy at 22.46 GHz,
indicating almost certain detection of radio emission from SN 2008ax.  The
inverted radio spectrum implies that the radio emission has likely been
caught on the rise.  Because of the unusual underluminous nature of SN 2008ax
(CBET 1285) and its resemblance in some characteristics to the peculiar type-
II supernova 1987A (CBETs 1285, 1290), the object warrants further study in
all wavelength bands.  Radio observations are continuing.


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                         (C) Copyright 2008 CBAT
2008 March 12                    (CBET 1299)              Daniel W. E. Green