Electronic Telegram No. 2156
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
CBAT@CFA.HARVARD.EDU (science)
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SUPERNOVA 2009ny
     Further to CBET 2151, E. Christensen, Gemini Observatory; A. J. Drake,
S. G. Djorgovski, A. Mahabal, M. J. Graham, and R. Williams, California
Institute of Technology; J. L. Prieto, Carnegie Observatories; M. Catelan,
Pontificia Universidad Catolica de Chile; and E. C. Beshore and S. M. Larson,
Lunar and Planetary Laboratory, University of Arizona, report the CRTS
discovery of a supernova in unfiltered Catalina Sky Survey (CSS) images.

    SN       2009 UT        R.A. (2000.0) Decl.      Mag.
    2009ny   Oct. 20.14   22 11 23.59  - 9 12 44.4   18.2

Further CSS magnitudes for 2009ny:  2009 Sept. 27.17, [20.8; Oct. 9.18, 19.7;
Nov. 11.11, 19.6; Dec. 19.07, [20.0.  The supernova matches the location of
a 23rd-magnitude object detected in a number of VR-filter images taken via
the NOAO Deep Wide Field Survey from 2000 to 2003.  A confirming spectrogram
(range 500-870 nm) was obtained using the Gemini South 8-m telescope (+ GMOS)
on Nov. 8 UT.  Cross-correlation with a library of supernova spectra using
the "SuperNova IDentification" code (Blondin and Tonry 2007, Ap.J. 666, 1024)
shows the best match for 2009ny to be with the type-Ib supernova 1999di at
one month past maximum light at redshift z = 0.057.  However, the spectral
lines are clearly weaker than the closest SNID match, and the photometry
suggests that the event was near two weeks past maximum.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
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                         (C) Copyright 2010 CBAT
2010 January 30                  (CBET 2156)              Daniel W. E. Green