Electronic Telegram No. 2011
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
CBAT@CFA.HARVARD.EDU (science)
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SUPERNOVAE 2009kn, 2009ko, 2009kq, AND 2009kr
     T. N. Steele, B. Cobb, and A. V. Filippenko, University of California,
Berkeley, report that inspection of a CCD spectrum (range 345-1000 nm),
obtained on Nov. 9 UT with the 3-m Shane reflector (+ Kast) at Lick
Observatory, shows that 2009kr (CBET 2006) is a young type-II supernova with
a very blue continuum and weak P-Cyg profiles of the hydrogen Balmer series;
the narrow Balmer emission lines mentioned by Tendulkar et al. (at website
URL http://www.astronomerstelegram.org/?read=2291) appear to be produced by a
superposed H II region, and the apparent width of the H-alpha emission line
is caused by blending with [N II] lines at 654.8 and 658.3 nm.  SN 2009kq
(CBET 2005) is a normal type-Ia supernova near 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 it is most similar to SN 2003cg at two days before maximum light, while
on the previous night, Tendulkar et al. (op.cit.) suggested that SN 2009kq
was about one week prior to maximum.  SN 2009kn (CBET 1997) is a type-IIn
supernova, with the hydrogen Balmer emission lines being very strong and
exhibiting a rather flat decrement.  These same emission lines also exhibit a
narrow absorption line within the emission profiles, indicating an outflowing
circumstellar medium; the H-alpha emission line has a FWHM of 1900 km/s.
SN 2009ko (CBET 1998) is a normal type-Ia supernova about a week after maximum
light; cross-correlation using SNID indicates that it is most similar to SN
1994M at about 8 days after maximum.


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                         (C) Copyright 2009 CBAT
2009 November 12                 (CBET 2011)              Daniel W. E. Green