Electronic Telegram No. 1950
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)
URL http://www.cfa.harvard.edu/iau/cbat.html


SUPERNOVAE 2009ja, 2009jb, 2009jc, 2009jd
     Further to CBET 1936, M. Catelan, Pontificia Universidad Catolica de
Chile; A. J. Drake, S. G. Djorgovski, A. Mahabal, M. J. Graham, and R.
Williams, California Institute of Technology; E. C. Beshore and S. M. Larson,
Lunar and Planetary Laboratory, University of Arizona; and E. Christensen,
Gemini Observatory, report the CRTS discovery of four apparent supernovae in
unfiltered Catalina Sky Survey (CSS) images:

 SN       2009 UT        R.A. (2000.0) Decl.       Mag.      Offset
 2009ja   Aug. 30.32   23 02 41.05  - 9 59 54.0    18.6    0".5 E, 1".0 N
 2009jb   Sep. 17.16   17 23 41.93  +30 29 50.2    17.4    3".1 E, 0".7 S
 2009jc   Sep. 17.37    1 02 43.63  -19 27 45.4    18.2
 2009jd   Sep. 19.33    0 29 56.04  - 4 34 50.7    18.4    12".6 E, 20".0 N

Further CSS magnitude estimates for 2009ja:  July 27.43 UT, [20.5; Aug. 26.33,
18.7; Sept. 10.27, 18.4; 21.25, 18.9.  Further CSS magnitude estimates for
2009jb:  July 31.25, [19.0; Aug. 20.20, 17.2.  Nothing was visible at the
position of 2009jc on a CCD image taken on 2008 Nov. 24.22 (limiting mag 20.4).
A spectrogram (range 380-900 nm) of 2009jc was obtained with the SMARTS 1.5-m
telescope on 2009 Sept. 23.25; cross-correlation with a library of supernova
spectra using the "SuperNova IDentification" code (SNID; Blondin and Tonry
2007, Ap.J. 666, 1024) shows 2009jc to be a type-Ia supernova most similar to
SN 1997dr at 17 days past maximum light.  Further CSS magnitude estimates for
2009jd:  2008 Nov. 6.18, [19.8; 2009 Aug. 30.38, 18.6.  Nothing is seen at
the position of 2009jd in past co-added Palomar-Quest exposures to mag 21.5.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2009 CBAT
2009 September 24                (CBET 1950)              Daniel W. E. Green