[IAUC] CBET 1310: 20080322 : SUPERNOVA 2008bf IN NGC 4055/4057

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                                                  Electronic Telegram No. 1310
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 2008bf IN NGC 4055/4057
     N. Morrell and M. Stritzinger, on the behalf of the Carnegie Supernova
Project, report that a spectrogram (range 360-940 nm) of 2008bf (cf. CBET
1307), obtained on Mar. 20.23 UT with the Magellan Clay 6.5-m telescope (+
LDSS3) at Las Campanas Observatory, shows it to be a type-Ia supernova
around a week before maximum.  The spectrum exhibits a blue continuum with
strong absorption due to Si II and a very prominent Ca II H and K feature.
Using the 'superfit' spectrum-comparison tool (Howell et al. 2005, Ap.J. 634,
1190), 2008bf appears to be most similar to supernova 1990N at ten days
before maximum.  From the minimum of the Si II 635.5-nm absorption line, an
expansion velocity of either 12400 km/s or 11500 km/s is derived, depending
on the the adopted redshift, which is 7203 km/s for NGC 4055 (de Vaucouleurs
et al. 1991, 3rd Reference Catalogue of Bright Galaxies, v. 3.9) or 6326
km/s for NGC 4057 (Mahdavi and Geller 2004, Ap.J. 607, 202).


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                         (C) Copyright 2008 CBAT
2008 March 22                    (CBET 1310)              Daniel W. E. Green