[IAUC] CBET 1257: 20080214 : SUPERNOVAE 2008W, 2008V, AND 2008ag

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                                                  Electronic Telegram No. 1257
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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SUPERNOVAE 2008W, 2008V, AND 2008ag
     M. Stritzinger and G. Folatelli, on the behalf of the Millennium Center
for Supernova Studies and the Carnegie Supernova Project, report that they
obtained spectra (range 400-1020 nm) of 2008V (cf. CBET 1238), 2008W (cf.
CBET 1238), and 2008ag (cf. CBET 1252) with the European Southern Observatory
New Technology Telescope (+ EMMI) on Feb. 13.1-13.3 UT.
     The spectrum of 2008V appears to be that of a type-IIb supernova around
a week past maximum light.  Using the "Supernova Identification" code (SNID;
Blondin and Tonry 2007, Ap.J. 666, 1024), 2008V is found to be most similar
to the spectrum of supernova 1993J, but with slightly-less-prevalent He I
features.  Adopting a host-galaxy recession velocity of 4113 km/s (Mathewson
et al. 1992, Ap.J. Suppl. 81, 413) for the host galaxy (NGC 1591), H-alpha
is measured to be blue-shifted by roughly 12,000 km/s.
     SN 2008W is a type-II plateau supernova around two weeks past explosion.
Adopting a host-galaxy recession velocity of 5727 km/s (Visvanathan and Yamada
1996, Ap.J. Suppl. 107, 521) for the host galaxy (MCG -03-22-7), H-beta is
measured to be blue-shifted by roughly 7700 km/s.
     The spectrum of 2008ag is also that of a type-II plateau supernova.
SNID indicates that 2008ag is very similar to supernovae 1999em and 1996bp
around 15-25 days past explosion.  Adopting a host-galaxy recession velocity
of 4439 km/s (Wong et al. 2006, MNRAS 371, 4) for the host galaxy (IC 4729),
H-beta is measured to be blue-shifted by roughly 7000 km/s.


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                         (C) Copyright 2008 CBAT
2008 February 14                 (CBET 1257)              Daniel W. E. Green