[IAUC] CBET 1851: 20090618 : SUPERNOVA 2009ga IN NGC 7678

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                                                  Electronic Telegram No. 1851
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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SUPERNOVA 2009ga IN NGC 7678
     T. N. Steele, B. Cenko, and A. V. Filippenko, University of California,
Berkeley, report that inspection of a CCD spectrum (range 340-1020 nm),
obtained on June 16 UT with the 3-m Shane reflector (+ Kast) at Lick
Observatory, shows that 2009ga (CBET 1839) is a young type-II supernova,
probably within 1-2 weeks after explosion.  The emission component of the
H-alpha line greatly dominates over the absorption component.  After removal
of the host-galaxy recession velocity of 3500 km/s (from NED; Chengalur et
al. 1993, Ap.J. 419, 30), the absorption minimum of the H-alpha line is
blueshifted by 9300 km/s.  Cross-correlation with a library of supernova
spectra using the "SuperNova IDentification" code (SNID; Blondin and Tonry
2007, Ap.J. 666, 1024) indicates that the spectrum of 2009ga is most
similar to that of the type-IIP supernova 2004et at one day past maximum
brightness.
     P. Challis, Harvard-Smithsonian Center for Astrophysics (CfA), on
behalf of the CfA Supernova Group, reports that a spectrum (range 320-850 nm)
of 2009ga, obtained on June 17 UT with the MMT (+ Blue Channel spectrograph),
shows it to be a type-IIP supernova.  Cross-correlation with a library of
supernova spectra using the SNID indicates that the spectrum of 2009ga best
resembles the type-IIP supernova 2004et at maximum brightness.


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                         (C) Copyright 2009 CBAT
2009 June 18                     (CBET 1851)              Daniel W. E. Green