[IAUC] CBET 1580: 20081124 : SUPERNOVAE 2008hh AND 2008hi

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                                                  Electronic Telegram No. 1580
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 2008hh AND 2008hi
     P. Challis, Harvard-Smithsonian Center for Astrophysics (CfA), on behalf
of the CfA Supernova Group, reports that a low-signal-to-noise-ratio spectrum
(range 350-740 nm) of 2008hh (CBET 1575), obtained on Nov. 23 UT by N. Wright
with the F. L. Whipple Observatory 1.5-m telescope (+ FAST), shows it to be a
type-Ic supernova at about maximum light.  Cross-correlation with a library
of supernova spectra using the "Supernova Identification" code (SNID; Blondin
and Tonry 2007, Ap.J. 666, 1024) indicates that 2008hh is most similar to
normal type-Ic supernovae at maximum light.
     F. Salgado, N. Morrell, and M. Stritzinger, on behalf of the Carnegie
Supernova Project, report that on Nov. 23.1 UT they obtained spectra (range
380-923 nm) of 2008hh (cf. CBET 1575) and 2008hi (cf. CBET 1578) with the
2.5-m du Pont telescope (+ WFCCD) at Las Campanas Observatory.  Comparison
with a library of supernovae spectra (Blondin and Tonry 2007, Ap.J. 666, 1024)
indicates that 2008hh is a type-Ic supernova, similar to 2004aw, near maximum
light.  Nebular emission lines are observed in the spectrum at a redshift of
z = 0.020, coincident with that of the host galaxy (0.0194 as measured by
Scneider et al. 1990, Ap.J. Suppl. 72, 245).  The spectrum of 2008hi is that
of a subluminous type-Ia supernova past maximum light.  The spectrum contains
Ti II absorption at 420 nm and Si II absorption at 615 nm.  They find the
spectrum of 2008hi to be similar to that of SN 2005ke around two weeks past
maximum; adopting a host-galaxy recession velocity of 4037 km/s (Fisher et
al. 1995, Ap.J. Suppl. 100, 69), Si II is measured to be blue-shifted by
roughly 10500 km/s.


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                         (C) Copyright 2008 CBAT
2008 November 24                 (CBET 1580)              Daniel W. E. Green