[IAUC] CBET 1201: 20080111 : SUPERNOVA 2008B IN NGC 5829

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                                                  Electronic Telegram No. 1201
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 2008B IN NGC 5829
     NOTE:  this text replaces that on CBET 1200.

     S. Blondin, Harvard-Smithsonian Center for Astrophysics (CfA), on
behalf of the CfA Supernova Group, reports that a spectrum (range 350-740 nm)
of 2008B (cf. CBET 1194), obtained on Jan. 10.55 UT by M. Calkins with the
F. L. Whipple Observatory 1.5-m telescope (+ FAST), shows it to be a type-IIn
supernova around maximum light.  Cross-correlation with a library of supernova
spectra using the "Supernova Identification" code (SNID; Blondin and Tonry
2007, Ap.J. 666, 1024) indicates that 2008B is most similar to the type-IIn
supernova 2000eo at two days before maximum.  The spectrum consists of a blue
continuum and emission lines of the Balmer series, with a narrow component of
about 500 km/s (FWHM for H_alpha) superposed on a weaker and broader component
of about 3800 km/s (FWHM for H_alpha).  The H_alpha and H_beta profiles also
display a narrow absorption component, present in early-time spectra of some
type-IIn supernovae.

     K. Ayani, Bisei Astronomical Observatory (BAO); and H. Yamaoka, Kyushu
University, report that a low-resolution (R about 1200 at H_alpha) spectrum
(range 400-750 nm) of 2008B, taken on Jan. 9.8 UT with the BAO 1.01-m
telescope, shows a rather blue continuum with a wide emission feature of
H_alpha (FWHM = 9000 km/s) showing a P-Cyg profile, which suggests that
2008B is a type-II supernova in the early stages.  A narrow H_alpha emission
(FWHM = 700 km/s), superimposed on the wider one, may suggest that the
supernova is surrounded by circumstellar matter.

     Corrigendum.  On CBET 1194, last line, FOR  from 1991 (limiting
magnitude 18.6).  READ  from 1991.



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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2008 CBAT
2008 January 11                  (CBET 1201)              Daniel W. E. Green