Electronic Telegram No. 2806 Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION CBAT Director: Daniel W. E. Green; Hoffman Lab 209; Harvard University; 20 Oxford St.; Cambridge, MA 02138; U.S.A. e-mail: cbatiau@eps.harvard.edu (alternate cbat@iau.org) URL http://www.cbat.eps.harvard.edu/index.html Prepared using the Tamkin Foundation Computer Network SUPERNOVA 2011fl IN IC 1584 = PSN J00471993+2749355 F. Ciabattari, S. Donati, G. Petroni, M. Rossi, and R. Simonetti, Borgo a Mozzano, Italy, report their discovery of an apparent supernova on unfiltered CCD images (limiting mag > 19.0) obtained on Aug. 22.08 (at mag 18.1 ) and 24.01 UT (when at mag 18.0) with a 0.5-m Newtonian telescope in the course of the Italian Supernovae Search Project. The new object is located at R.A. = 0h47m19s.93, Decl. = +27d49'35".5 (equinox 2000.0; astrometry with respect to UCAC-2 stars), which is 18" east and 5" south of the center of the galaxy IC 1584. Nothing is visible at this position on their images from Sept. and Dec. 2010 (limiting mag 18.8) or on digitized Palomar Sky Survey plates from 1987 Aug. 21 (J plate, limiting mag 20.3) and 1990 Oct. 24 (limiting mag 20.3). The variable was designated PSN J00471993+2749355 when it was posted at the Central Bureau's TOCP webpage and is here designated SN 2011fl based on the spectroscopic report below. Additional unfiltered CCD magnitudes for 2011fl: Aug. 25.266 UT, 18.3 (Joseph Brimacombe, Cairns, Australia; position end figures 19s.84, 36".0; image posted at URL http://www.flickr.com/photos/43846774@N02/6080840385/); 30.102, 18.5 (Federica Luppi, Varese, Italy, 0.38-m f/6.8 reflector; position end figures 19s.86, 35".0; image posted at the following website URL: http://www.astrogeo.va.it/pub/TOCP/PSN_I1584.jpg). L. Magill, Queen's University, Belfast, and Isaac Newton Group; R. Kotak and S. Smartt, Queen's University, Belfast; and A. Pastorello, Osservatorio Astronomico di Padova, Istituto Nazionale di Astrofisica, report that an optical spectrum (range 330-800 nm) of PSN J00471993+2749355 = SN 2011fl was obtained at the William Herschel Telescope (+ ISIS spectrograph) by K. Maguire on Aug. 31.24 UT. Deep Na I D lines suggest that the supernova suffers from high extinction. Cross-correlation with a library of supernova spectra using the "Gelato" code (Harutyunyan et al. 2008, A.Ap. 488, 383), suggests a type-Ib supernova identification, matching with SN 2005bf (Anupama et al. 2005, Ap.J. 631, L125) at an epoch of about 60 days post-maximum. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2011 CBAT 2011 September 3 (CBET 2806) Daniel W. E. Green