[IAUC] CBET 1849: 20090617 : SUPERNOVAE 2009fw AND 2009gc

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                                                  Electronic Telegram No. 1849
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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CBAT en CFA.HARVARD.EDU (science)
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SUPERNOVAE 2009fw AND 2009gc
     J. M. Silverman, D. Poznanski, A. V. Filippenko, and R. Chornock,
University of California, Berkeley; and I. Arcavi, Weizman Instiute of
Science, report that inspection of a CCD spectrum (range 340-1000 nm),
obtained on June 17 UT with LRIS on the Keck I 10-m telescope, shows that
2009fw (CBET 1836) is a normal type-Ia supernova.  After removing the
host-galaxy recession velocity (8462 km/s; Da Costa, et al. 1991, Southern
Sky Reshift Survey:  The Catalogue), the absorption minimum of the Si II
635.5-nm feature is found to be blueshifted by about 11800 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 2009fw is about one week past maximum light.  A noisy
spectrum of 2009gc (CBET 1841) shows that it is probably a type-II
supernova.  The strong emission feature identified as H-alpha greatly
dominates over the corresponding absorption component.


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                         (C) Copyright 2009 CBAT
2009 June 17                     (CBET 1849)              Daniel W. E. Green