[IAUC] CBET 1909: 20090817 : SUPERNOVA 2009hy, 2009hr, AND 2009hs

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                                                  Electronic Telegram No. 1909
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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SUPERNOVA 2009hy, 2009hr, AND 2009hs
     T. N. Steele, S. B. Cenko, W. Li, J. M. Silverman, and A. V. Filippenko,
University of California, Berkeley, report that inspection of CCD spectra
(range 340-1000 nm), obtained on Aug. 14 UT with the 3-m Shane reflector (+
Kast) at Lick Observatory, shows that SN 2009hy (CBET 1895) is a type-Ic
supernova; cross-correlation with a library of supernova spectra using the
"SuperNova IDentification" code (SNID; Blondin and Tonry 2007, Ap.J. 666,
1024) indicates that 2009hy is similar to SN 2004aw shortly after maximum
light.  SN 2009hr (CBET 1891) is a normal type-Ia supernova; cross-correlation
using SNID indicates that it is about 40 days after maximum light, and that
it is most similar to SN 1998bu at 41 days after maximum.  SN 2009hs (CBET
1892) is a type-Ia supernova, possibly similar to the subluminous supernova
1991bg (Filippenko et al. 1992, A.J. 104, 1543).  After removal of 2009hs'
host-galaxy recession velocity of 8200 km/s (Wegner et al. 1999, MNRAS 305,
259), the absorption minimum of the Si II 635.5-nm line is found to be
blueshifted by 8900 km/s; cross-correlation using SNID indicates that 2009hs
is about one week after maximum light, and is most similar to the 1991bg-like
object 1997ba at 8 days after maximum.


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                         (C) Copyright 2009 CBAT
2009 August 17                   (CBET 1909)              Daniel W. E. Green