[IAUC] CBET 1521: 20080928 : SUPERNOVA 2008fw IN NGC 3261

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                                                  Electronic Telegram No. 1521
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 2008fw IN NGC 3261
     L. A. G. Monard, Pretoria, South Africa, reports his discovery of an
apparent supernova (mag 14.3 +/- 0.2) on an unfiltered CCD image taken on
Sept. 19.130 UT.  The new object is located at R.A. = 10h28m55s.97, Decl.
= -44o39'55".6, which is 52" west and 30" south of the galaxy core of NGC
3261.  There is a red star of magnitude about 18 very close to this
position, with USNO-B1.0-catalogue position end figures 55s.95, 56".4.
Additional unfiltered CCD magnitudes for 2008fw:  July 28.687, [18;
Sept. 20.128, 14.2; 22.125, 14.1; 23.118, 14.2; 24.118, 14.2; 26.123, 14.2.
Also on Sept. 22.125, V = 14.0, and B-V around -0.2.
     N. Morrell, on behalf of the Carnegie Supernova Project, reports on
spectroscopy (range 380-920 nm) obtained on Sept. 28.39 UT with the Las
Campans du Pont 2.5-m telescope (+ WFCCD spectrograph):  Inspection of
the spectrum shows that 2008fw is a type-Ia supernova near maximum light.
Comparison with a library of supernova spectra via the "Supernova
Identification" code (Blondin and Tonry 2007, Ap.J. 666, 1024) gives
excellent agreement with a number of normal type-Ia supernovae at ages
between one week before and 3-4 days after maximum brightness.  An expansion
velocity of 9700 km/s is derived from the minimum of the Si II 635.5-nm
absorption, when the NED redshift of 2563 km/s is assumed for the host galaxy
(Koribalski et al. 2004, A.J. 128, 16).


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                         (C) Copyright 2008 CBAT
2008 September 28                (CBET 1521)              Daniel W. E. Green