[IAUC] CBET 1359: 20080430 : SUPERNOVA 2008bx IN MCG +07-31-4

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                                                  Electronic Telegram No. 1359
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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SUPERNOVA 2008bx IN MCG +07-31-4
     M. C. Bentz and J. L. Walsh, University of California, Irvine; and J.
M. Silverman, T. N. Steele, and A. V. Filippenko, University of California,
Berkeley, report that inspection of CCD spectra (range 330-1050 nm), obtained
on Apr. 28 UT with the Shane 3-m telescope at Lick Observatory, reveals that
2008bx (CBET 1348) is a type-II supernova.  Several weak, broad spectral
features are present on top of a relatively featureless continuum and appear
mostly in absorption.  Removing a host-galaxy recession velocity of 2800 km/s
(from a narrow emission lines), the minimum of the H-beta absorption is
blueshifted by about 10000 km/s.
      S. Blondin, Harvard-Smithsonian Center for Astrophysics (CfA), on behalf
of the CfA Supernova Group, reports that a spectrum (range 350-740 nm) of
2008bx, obtained on Apr. 29.32 UT by P. Berlind with the F. L. Whipple
Observatory 1.5-m telescope (+ FAST), shows it to be a young type-II
supernova.  The spectrum consists of a blue continuum with shallow P-Cyg
profiles of the Balmer series and He I (587.6 nm).  Adopting a recession
velocity of 2518 km/s for the host galaxy (from de Vaucouleurs et al. 1991,
Third Ref. Cat. of Bright Galaxies), the maximum absorption in the H_beta
line (rest 486.1 nm) is blueshifted by roughly 9000 km/s.


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                         (C) Copyright 2008 CBAT
2008 April 30                    (CBET 1359)              Daniel W. E. Green