Electronic Telegram No. 677
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)
URL http://cfa-www.harvard.edu/iau/cbat.html


SUPERNOVA 2006jc IN UGC 4904   [slight revision to the text of CBET 676]
     M. Modjaz, S. Blondin, R. Kirshner, and P. Challis, Harvard-Smithsonian
Center for Astrophysics; and T. Matheson, National Optical Astronomy
Observatory, report that a spectrogram (range 350-740 nm) of SN 2006jc,
obtained by E. Mamajek on Oct. 17.50 UT with the F. L. Whipple Observatory
1.5-m telescope (+ FAST), shows it to be a peculiar supernova probably of
type Ib/c with emission lines of He I, essentially agreeing with the
assessments by Crotts et al. (CBET 672) and by Benetti et al. (CBET 674).
The spectrum is similar to that of SN 1999cq (Matheson et al. 2000, A.J. 119,
2303); however, notable differences from SN 1999cq include a very blue
continuum; additional emission lines consistent with He I 388.9-, 447.1-, and
501.5-nm (rest) that have widths of 1500-6500 km/s (FWHM); and the absence of
the broad peak at around 540 nm.  A plot showing the comparison between
2006jc and 1999cq can be viewed via the webpage
http://cfa-www.harvard.edu/oir/Research/supernova/spectra/sn06jc_comp.gif
and the spectrum at  .../spectra/sn2006jc-20061017.flm.gif


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2006 CBAT
2006 October 18                  (CBET 677)               Daniel W. E. Green