Electronic Telegram No. 4182 Central Bureau for Astronomical Telegrams Mailing address: 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 2015ai IN UGC 8734 = PSN J13480490+6149153 E. Briggs, R. Post, T. Puckett, and J. Newton report the discovery of an apparent supernova (mag 16.3) on unfiltered CCD images (limiting mag 19.0) taken with a 0.60-m reflector at Mayhill, NM, U.S.A., on July 2.240 UT in the course of the Puckett Observatory Supernova Search. The new object is located at R.A. = 13h48m04s.90, Decl. = +61o49'15".3 (equinox 2000.0), which is 7".0 west and 20".2 south of the center of UGC 8734. An image of the variable is posted at website URL http://possdata.com/PSNJ13480490+6149153.jpg. The variable was designated PSN J13480490+6149153 when it was posted at the Central Bureau's TOCP webpage and is here designated SN 2015ai based on the spectroscopic confirmation reported below. G. Masi writes that his images taken remotely on July 5.964 with a 43-cm telescope at Ceccano, Italy, show 2015ai at mag 16.5 with position end figures 04s.90, 15".7. G. Terreran, M. Turatto, S. Benetti, E. Cappellaro, N. Elias-Rosa, P. Ochner, A. Pastorello, L. Tartaglia, and L. Tomasella, Osservatorio Astronomico di Padova, Istituto Nazionale di Astrofisica, report that an optical spectrogram (range 340-820 nm; resolution 1.4 nm) of PSN J13480490+6149153 = SN 2015ai, obtained on Aug. 12.80 UT with the Asiago 182-cm Copernico Telescope (+ AFOSC) in the framework of the Asiago Transient Classification Program (Tomasella et al. 2014, A.N. 335, 841), shows that this a type-Ia supernova, about 5 weeks after maximum light. Adopting a redshift z = 0.031 (Falco et al. 1999, PASP 111, 438; from NED) for the host galaxy, UGC 8734, the best match is found with the normal type-Ia supernova 2003du and with the 1991T-like supernova 1999aa. Classification was done with GELATO (Harutyunyan et al. 2008, A.Ap. 488, 383) and SNID (Blondin and Tonry 2007, Ap.J. 666, 1024). The Asiago classification spectra are posted at URL http://sngroup.oapd.inaf.it. NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2015 CBAT 2015 November 17 (CBET 4182) Daniel W. E. Green