Electronic Telegram No. 2910 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 2011ia IN MCG +11-12-23 = PSN J09450355+6415366 F. Ciabattari, S. Donati, E. Mazzoni, G. Petroni, and M. Rossi, Borgo a Mozzano, Italy, report their discovery of an apparent supernova (mag 16.2) on unfiltered CCD images obtained on Nov. 18.21 and 19.01 UT with a 0.5-m Newtonian reflector in the course of the Italian Supernovae Search Project. The new object is located at R.A. = 9h45m03s.55, Decl. = +64d15'36".6 (equinox 2000.0; astrometry with respect to UCAC-2 stars) which is 2" east and 16" north of the center of the galaxy MCG +11-12-23 (= PGC 27923). The variable was designated PSN J09450355+6415366 when it was posted at the Central Bureau's TOCP webpage and is here designated SN 2011ia based on the spectroscopic confirmation reported below. Additional magnitudes for 2011ia (via unfiltered CCD unless noted otherwise): 1989 Dec. 23, [20.3 (Palomar Sky Survey, F plate; via Ciabattari); 1995 Mar. 26, [20.3 (Palomar Sky Survey, J plate; via Ciabattari); Nov. 19.117, 15.1 (Federica Luppi and Luca Buzzi, Varese, Italy; position end figures 03s.40, 35".0; reference stars from PPMXL catalogue; image posted at URL http://www.astrogeo.va.it/pub/TOCP/PSN_G11-12-23.jpg); 19.316, 15.3 (R. A. Koff, Bennett, CO, USA; Meade 0.25-m f/10 reflector + Apogee AP-47p camera; limiting magnitude 18.4; position end figures 03s.36, 35".5; UCAC3 reference stars); 20.512, 15.6 (Joseph Brimacombe, Cairns, Australia; luminance filter; position end figures 03s.47, 35".0; image posted at website URL http://www.flickr.com/photos/43846774@N02/6372205161/). S. Valenti, A. Pastorello, S. Benetti, L. Tomasella, F. Bufano, and P. Ochner, Istituto Nazionale di Astrofisica, Osservatorio Astronomico di Padova, on behalf of a larger collaboration, report that a spectrogram of PSN J09450355+6415366 = SN 2011ia, obtained on Nov. 20.08 UT with the 1.82-m Copernico Telescope (+ AFOSC; range 340-790 nm, resolution 2.2 nm), suggests that it is a type-Ia supernova. Cross-correlation with a library of supernova spectra through the "Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) indicates that 2011ia is a type-Ia supernova about 9 days before its B-band maximum. Adopting a redshift z = 0.019, from the position of the minimum of the Si II 635.5-nm line, a velocity for the ejected material of about 11500 km/s is derived. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2011 CBAT 2011 November 22 (CBET 2910) Daniel W. E. Green