[IAUC] CBET 1756: 20090406 : SUPERNOVA 2009by IN UGC 6260

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                                                  Electronic Telegram No. 1756
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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SUPERNOVA 2009by IN UGC 6260
     K. Konishi, Y. Ihara, and K. Tokita, University of Tokyo; N. Morimoto,
Tohoku University; and T. Hattori, National Astronomical Observatory of Japan,
report that a spectrogram (range 370-900 nm) of 2009by (cf. CBET 1748),
obtained on Apr. 4.28 UT with the 8.2-m SUBARU Telescope (+ FOCAS), shows it
to be a type-II supernova.  Their recently-developed identification code
suggests that the spectrum is best fitted to that of the type-IIP supernova
1999em at five days after the explosion (Elmhamdi et al. 2003, MNRAS 338,
938).  There are narrow emission-line components of H_alpha and H_beta,
corresponding to z = 0.021 +/- 0.001; it is unclear whether these narrow
components originate from the H II region of the host galaxy or are intrinsic
to the supernova.  Thus, it the possibility cannot be excluded that this
supernova is of type IIn.


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                         (C) Copyright 2009 CBAT
2009 April 6                     (CBET 1756)              Daniel W. E. Green