[IAUC] CBET 881: 20070313 : SUPERNOVA 2007ak IN UGC 3293

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                                                  Electronic Telegram No. 881
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 2007ak IN UGC 3293
     J. M. Silverman, T. N. Steele, and A. V. Filippenko, University of
California, Berkeley, report that inspection of CCD spectra (range 340-1050
nm), obtained on Mar. 13 UT with the Lick 3-m telescope (+ Kast), shows
that 2007ak (cf. CBET 875) is a type-IIn supernova.  The spectrum exhibits
strong, very narrow (FWHM about 400 km/s) H-alpha emission on a relatively
featureless continuum, and the other members of the hydrogen Balmer series
are weak or absent (though the spectrum is noisy there).  SN 2007ak thus
resembles the type-IIn supernova 2002kg (cf. IAUC 8051) and its brethren.
Arguments have previously been made that type-IIn events may, at least in
some cases, be superoutbursts of luminous variable stars (e.g., Filippenko
et al. 1995, A.J. 110, 2261; Van Dyk et al. 2000, PASP 112, 1532).


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                         (C) Copyright 2007 CBAT
2007 March 13                    (CBET 881)               Daniel W. E. Green