[IAUC] CBET 1577: 20081120 : SUPERNOVAE 2008gy AND 2008hg

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                                                  Electronic Telegram No. 1577
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 2008gy AND 2008hg
     G. Folatelli, F. Forster, and M. Stritzinger, on behalf of the Carnegie
Supernova Project and Millennium Center for Supernova Studies collaboration,
report that they obtained spectra (range 340-602 nm) of 2008gy (cf. CBET
1565) and 2008hg (cf. CBET 1571, 1573) with the New Technology Telescope (+
EFOSC2) at La Silla on Nov. 19.0-19.1 UT.
     The spectrum of 2008gy shows it to be a type-Ia supernova, two to three
weeks after maximum light.  With the aid of the "Supernova Identification"
code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024), a redshift of 0.029 is
found for 2008gy.  SNID provides the best match with the type-Ia supernova
1990N at 18 days past maximum.  Adopting the redshift given above, the blend
of the Ca II H and K lines is measured to be blueshifted by about 13400 km/s.
     The spectrum of SN 2008hg is that of a young type-IIp supernova.  SNID
provides matches with spectra of the type-IIp supernovae 1999em and 2005cs,
a few days after the explosion.  Adopting a recession velocity of 5684 km/s
for the host galaxy (IC 1720; Mathewson and Ford 1996, Ap.J. Suppl. 107, 97),
an expansion velocity of 8200 km/s is derived from the absorption minimum of
the H-beta line.


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                         (C) Copyright 2008 CBAT
2008 November 20                 (CBET 1577)              Daniel W. E. Green