[IAUC] CBET 951: 20070429 : SUPERNOVA 2007ca IN MCG -02-34-61

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                                                  Electronic Telegram No. 951
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 2007ca IN MCG -02-34-61
     V. Stanishev, Physics Department, Stockholm University, reports
that a spectrum of 2007ca (cf. CBET 945), obtained on Apr. 27.93 UT
with the Nordic Optical Telescope (+ ALFOSC; range 350-910 nm) by A.
Tziamtzis, confirms the classification on CBET 947 that the supernova
is of type Ia.  The spectrum is very similar to that of SN 2003du at
about a week before maximum (Stanishev et al. 2007, A.Ap., in press),
but it was necessary to be de-reddened for E(B-V) = 0.4.  The
comparison can be seen at the following World Wide Web URL:
http://www.physto.se/~vall/sne_classified.html).  A narrow interstellar
Na I 589.3-nm absorption is detected at the redshift of the host galaxy
(4217 km/s; Catinella et al. 2005, A.J. 130, 1037) with an equivalent
width of about 0.16 nm.  The blue-shift of the Si II line (635.5 nm)
minimum is about 11500 km/s (corrected for the host-galaxy velocity),
and it is interesting to note that the red wing of the line has a
well-visible shoulder.  A high-velocity component that is blue-shifted
by about 20000 km/s is clearly seen in the Ca II infrared triplet line.


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                         (C) Copyright 2007 CBAT
2007 April 29                    (CBET 951)               Daniel W. E. Green