Electronic Telegram No. 2685 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 2011bd IN NGC 6473 = PSN J17470632+5718047 A. Langoussis, J. Newton, and T. Puckett report the discovery of an apparent supernova (mag 16.0) on unfiltered CCD images (limiting mag 19.1) taken with a 0.40-m reflector at Portal, AZ, U.S.A., on Mar. 24.479 UT, in the course of the Puckett Observatory Supernova Search. The new object was designated PSN J17470632+5718047 when posted on the Central Bureau's TOCP webpage and is designated SN 2011bd here based on the spectroscopic report below. SN 2011bd is located at R.A. = 17h47m06s.32, Decl. = +57o18'04".7 (equinox 2000.0), which is 5".9 east and 0".2 south of the center of NGC 6473. Puckett has posted an image at http://www.possdata.com/PSNJ17470632+5718047.jpg. Additional unfiltered CCD magnitudes for 2011bd: Mar. 20, [18.9 (Puckett); 25.507, 16.0 (Puckett); 29.460, 16.2 (Joseph Brimacombe, Cairns, Australia; remotely using a 51-cm RCOS telescope + STL11K camera at New Mexico Skies Observatory, Mayhill, NM, U.S.A.); Apr. 2.154, 16.5: (Xavier Bros, Ager, Spain, 0.35-m telescope; position end figures 06s.51, 03".2). Brimacombe has posted his image at http://www.flickr.com/photos/43846774@N02/5576401868/. G. H. Marion, Harvard-Smithsonian Center for Astrophysics (CfA), on behalf of the CfA Supernova Group, reports that a spectrum (range 340-740 nm) of PSN J17470632+5718047 = SN 2011bd was obtained on Apr. 2 UT by Marion with the F. L. Whipple Observatory 1.5-m telescope (+ FAST). Cross-correlation with a library of supernova spectra using the "Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) shows that 2011bd is a type-Ia supernova a few days after maximum light. Using an estimated redshift of z = 0.0281, measured from host-galaxy emission lines, the velocity of the Si II 635.5-nm feature is estimated to be approximately 10400 km/s. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2011 CBAT 2011 April 10 (CBET 2685) Daniel W. E. Green