2009CBET.1960....1D

Further to CBET 1958, A. J. Drake, S. G. Djorgovski, A. Mahabal, M. J. Graham and R. Williams, California Institute of Technology; T. A. Fatkhullin, A. S. Moskvitin, V.N. Komarov, Special Astrophysical Observatory, Russian Academy of Sciences; M. Catelan, Pontificia Universidad Catolica de Chile; E. C. Beshore and S. M. Larson, Lunar and Planetary Laboratory, University of Arizona; and E. Christensen, Gemini Observatory, report the CRTS discovery of a supernova in unfiltered Catalina Sky Survey (CSS) images:

---------------------------------------------------------------------------— SN 2009 UT R.A. (2000.0) Decl. Mag. Offset ---------------------------------------------------------------------------— 2009ji Sep. 23.14 15 54 52.48 +32 05 05.6 17.9 1".5 E, 2".7 N ---------------------------------------------------------------------------—

Nothing was visible at this position on a CSS image taken on Aug. 2.25 UT (limiting mag 20.9). Confirming spectroscopic observations (range 380-770 nm) of 2009ji were taken on Sept. 25.75 with the BTA 6-m telescope. Cross-correlation with a library of supernova spectra using the "SuperNova IDentification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) shows this to be a type-Ia supernova, most similar to SN 2003du at 11 days past maximum light. The redshift is estimated to be z = 0.048.