[IAUC] CBET 962: 20070514 : SUPERNOVA 2007cg IN ESO 508-G75

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                                                  Electronic Telegram No. 962
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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SUPERNOVA 2007cg IN ESO 508-G75
     S. Blondin, M. Hicken, M. Modjaz, R. Kirshner, and P. Challis,
Harvard-Smithsonian Center for Astrophysics, report that a spectrum
(range 350-740 nm) of 2007cg (cf. CBET 960), obtained on May 14.26 UT
by W. Brown with the F. L. Whipple Observatory 1.5-m telescope (+ FAST),
shows it to be a highly reddened type-Ia supernova before maximum light.
Cross-correlation with a library of supernova spectra shows that 2007cg
is most similar to SN 1999ee at one week before maximum light.  Adopting
a recession velocity of 9952 km/s for the host galaxy of 2007cg (from
Mathewson and Ford 1996, Ap.J. Suppl. 107, 97), the maximum absorption
in the Si II line (rest 635.5 nm) is blueshifted by roughly 13000 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 2007 CBAT
2007 May 14                      (CBET 962)               Daniel W. E. Green