Electronic Telegram No. 672
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)
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SUPERNOVA 2006jc IN UGC 4904
     A. Crotts, Columbia University; J. Eastman, D. DePoy, and J. L.
Prieto, Ohio State University; and P. Garnavich, University of Notre
Dame, report that spectra of the possible bright supernova in UGC 4904
(cf. CBET 666) were obtained with the Hiltner 2.4-m telescope (+ CCDS
spectrograph) at MDM Observatory on Oct. 11.5 UT.  The reduced spectra
show many broad features consistent with a supernova spectrum.
Assuming a recesion velocity for the host galaxy of 1670 km/s
(Nordgren et al. 1997, A.J. 114, 913), several emission features are
found to be consistent with He I 381.9-, 447.1-, 587.5-, and 706.5-nm.
The spectrum also shows a very weak absorption feature consistent with
H-alpha.  This object is likely a type-Ib supernova from the strong He
I features present in the spectrum.
     R. Fesen, D. Milisavljevic, and G. Rudie, Dartmouth College,
report that a low-dispersion spectrum (range 450-700 nm) of the
possible supernova in UGC 4904, taken with the MDM 2.4-m telescope
on Oct. 12.5 UT, shows an apparent type-Ib supernova spectrum.  Broad
emission lines with expansion velocities around 5000 km/s are detected
with peaks at 506.1, 595.2, and 638.4 nm, which can be attributed to
[O III] 500.7-nm, He I 587.6-nm, and [O I] 630.0-nm.  Broad emission
extends redward from [O III] to 553 nm, with the apparent He I feature
showing a sharp emission line at 590.6 nm.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
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                         (C) Copyright 2006 CBAT
2006 October 12                  (CBET 672)               Daniel W. E. Green