Electronic Telegram No. 2676 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 2011at = PSN J09285756-1448206 L. Cox, J. Newton, and T. Puckett report the discovery of an apparent supernova (mag 14.5) on an unfiltered CCD image (limiting mag 19.0) taken with a 0.40-m reflector at Portal, AZ, U.S.A., on Mar. 10.214 UT in the course of the Puckett Observatory Supernova Search. The new object was designated PSN J09285756-1448206 when posted on the Central Bureau's TOCP webpage and is here designated SN 2011at based on the spectroscopic reports below. SN 2011at is located at R.A. = 9h28m57s.56, Decl. = -14d48'20".6 (equinox 2000.0), which is 20".4 east and 6".3 north of the center of PGC 26905 = MCG -02-24-27. Nothing is visible at this position on images taken by Puckett on Feb. 13 (limiting mag 19.1). F. Bufano, Istituto Nazionale di Astrofisica (INAF), Osservatorio Astronomico di Catania; S. Benetti, INAF, Osservatorio Astronomico di Padova; and A. Pastorello, Queen's University, Belfast, on behalf of a larger collaboration, report that a spectrogram (range 200-500 nm) of PSN J09285756-1448206 = 2011at was obtained on 2011 Mar. 11.81 UT with the Swift satellite (+ UVOT). The spectrum of 2011at is consistent with that of a type-Ia supernova around maximum, showing strong absorption features mainly due to Ca II H and K, Si II, Fe III, and Co III and resembling ultraviolet spectra of SN 2005cf at similar epochs (Bufano et al. 2009, Ap.J. 700, 1456). A multi-wavelength follow-up campaign of observing 2011at, using numerous ground-based facilities, is in progress. G. H. Marion, Harvard-Smithsonian Center for Astrophysics (CfA), on behalf of the CfA Supernova Group, report that a spectrum (range 340-740 nm) of PSN J09285756-1448206 = 2011at was obtained on Mar. 12 UT by M. Calkins 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 the object is a type-Ia supernova a few days before maximum light. The velocity of the Si II 635.5-nm feature, measured at the absorption minimum, is 12100 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 March 12 (CBET 2676) Daniel W. E. Green