[IAUC] CBET 1616: 20081211 : SUPERNOVAE 2008hv AND 2008ia

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                                                  Electronic Telegram No. 1616
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 2008hv AND 2008ia
     [Editor's note:  this text replaces that on CBET 1615.]
     G. Folatelli and F. Forster, on behalf of the Carnegie Supernova
Project and Millennium Center for Supernova Studies collaboration, report
that they obtained spectra (range 330-930 nm) of SN 2008hv (CBET 1601,
1603, 1604) and SN 2008ia (CBET 1612) with the New Technology Telescope (+
EFOSC2) at La Silla on Dec. 10.2-10.3 UT.  The spectrum of 2008hv shows this
to be a type-Ia supernova at about one week before maximum light.  The
"Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666,
1024) yields a good match to the type-Ia supernova 1994D at 9 days before
maximum.  Adopting a recession velocity of 3762 km/s for the host galaxy
(NGC 2765; Wegner et al. 2003, A.J., 126, 2268), the Si II 635.5-nm blend
appears to be blueshifted by about 11400 km/s.  The blend of the Ca II H
and K lines shows a double-minimum structure, suggesting two absorbing
components centered at 18000 and 22000 km/s.
     SN 2008ia is also a type-Ia supernova before maximum light.  The best
match from SNID is with a spectrum of SN 1994D at 3 days before maximum;
SNID also provides with an estimate of the redshift of z = 0.022.  Adopting
this redshift, the absorption minimum of the Si II 635.5-nm doublet
indicates an expansion velocity of roughly 11300 km/s.  From the absorption
minimum of the Ca II H and K blend, two components also can be identified
that appear to be blueshifted by about 18000 and 22000 km/s.


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                         (C) Copyright 2008 CBAT
2008 December 11                 (CBET 1616)              Daniel W. E. Green