[IAUC] CBET 684: 20061021 : SUPERNOVA 2006ke IN UGC 3365 [slight revision to text of CBET 683]

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                                                  Electronic Telegram No. 684
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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SUPERNOVA 2006ke IN UGC 3365  [slight revision to text of CBET 683]
     S. Blondin, M. Modjaz, R. Kirshner, and P. Challis, Harvard-Smithsonian
Center for Astrophysics, report that a spectrum (range 350-740 nm) of 2006ke
(cf. CBET 682), obtained on Oct. 21.50 UT by W. Peters with the F. L. Whipple
Observatory 1.5-m telescope (+ FAST), shows it to be a reddened type-Ia
supernova around maximum light.  Cross-correlation with a library of
supernova spectra shows that 2006ke is most similar to the subluminous
supernova 1999by at -3 days from maximum light.  Given the estimated
magnitude of the event (cf. CBET 682), and assuming no peculiar motion, the
absolute visual magnitude is at most roughly -16.  Even allowing for
significant reddening does not yield an absolute magnitude consistent with a
normal type-Ia supernova at that phase, thereby confirming the subluminous
nature of this event.  Adopting a recession velocity of 5150 km/s for the
host galaxy (from Falco et al. 2000, "The Updated Zwicky Catalog", vol. 1),
the maximum absorption in the Si II line (rest 635.5 nm) is blueshifted by
roughly 11000 km/s.  Also, interstellar Na I D absorption at the redshift of
the host galaxy is visible in the spectrum with an equivalent width of 0.3 nm.


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                         (C) Copyright 2006 CBAT
2006 October 21                  (CBET 684)               Daniel W. E. Green