[IAUC] CBET 1918: 20090821 : SUPERNOVA 2009ig IN NGC 1015

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                                                  Electronic Telegram No. 1918
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 2009ig IN NGC 1015
     Further to CBET 1915, I. Kleiser, S. B. Cenko, W. Li, and A. V.
Filippenko, University of California, report the LOSS discovery of an
apparent supernova on unfiltered KAIT images:

 SN       2009 UT       R.A. (2000.0) Decl.      Mag.      Offset
 2009ig   Aug. 20.48   2 38 11.61  - 1 18 45.1   17.5    0".6 E, 22".0 N

Nothing was visible at this position on Aug. 16.46 (limiting mag 18.7).
     H. Navasardyan, E. Cappellaro, and S. Benetti, Istituto Nazionale di
Astrofisica, Osservatorio Astronomico di Padova, report that a spectrogram
of 2009ig, obtained on Aug. 21.08 UT with the Asiago 1.82-m telescope (+
AFOSC; range 375-775 nm; resolution 2.4 nm), is dominated in the red
region by a deep and broad Si II 635.5-nm feature (measured at 589.1 nm),
and in the blue region by strong features due to Mg II (418.4 nm), and Si
II + Fe II (about 470.5 nm).  Assuming a recession velocity of 2629 km/s
for the host galaxy (H I Parkes All Sky Survey Final Catalogue, 2006; via
NED) the minimum of the Si II 635.5-nm absorption implies a record-high
expansion velocity of about 24500 km/s.  This indicates that the object
is a type-Ia supernova caught soon after explosion, with some similarity
to early spectra of SN 2002bo (Benetti et al. 2004, MNRAS 348, 261),
although Si II 597.2-nm and S II 564.0-nm are not yet present.


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                         (C) Copyright 2009 CBAT
2009 August 21                   (CBET 1918)              Daniel W. E. Green