[IAUC] CBET 1329: 20080408 : SUPERNOVAE 2008bm, 2008bp, AND 2008bq

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                                                  Electronic Telegram No. 1329
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 2008bm, 2008bp, AND 2008bq
     M. Stritzinger and N. Morrell, on behalf of the Carnegie Supernova
Project (CSP), report that they have obtained spectra (range 380-920 nm) of
2008bm (cf. CBET 1320), 2008bp (cf. CBET 1326), and 2008bq (cf. CBET 1328)
with the Las Campanas Observatory DuPont Telescope (+ WFCCD) on Apr. 7.1-7.3
UT.  Supernova 2008bm appears to be a type-IIn supernova, a couple of months
past explosion.  The spectrum of 2008bm is nearly identical to a spectrum of
the type-IIn supernova 2005kj taken by the CSP on 2006 Feb. 13.1.
     SN 2008bp appears to be a highly reddened young type-II-plateau supernova.
The spectrum consists of a red continuum with strong H-alpha emission and a
relatively weak H-beta absorption.  Using the "Supernova Identification" code
(SNID; Blondin and Tonry 2007, Ap.J. 666, 1024), they find 2008bp to be
similar to supernova 2004et around two weeks past explosion.  Adopting a
host-galaxy recession velocity of 2723 km/s (de Vaucouleurs et al., Third
Reference Catalogue of Bright Galaxies, Version 3.9) for the host galaxy, NGC
3095, H-beta is measured to be blue-shifted by roughly 9000 km/s.
     The spectrum of 2008bq indicates that it is a type-Ia supernova near
maximum light.  With the aid of SNID, they find 2008bq to be similar to
supernova 2003du at one day before maximum light.  Adopting a host-galaxy
recession velocity of 10193 km/s (derived from emission lines in a spectrum
of the host galaxy), the Si II absorption feature yields an expansion
velocity of roughly 11000 km/s.


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                         (C) Copyright 2008 CBAT
2008 April 8                     (CBET 1329)              Daniel W. E. Green