R. Quimby, California Institute of Technology, on behalf of a large collaboration called the Palomar Transient Factory'' (PTF; including S. Kulkarni, N. Law, M. Kasliwal, E. Ofek, P. Nugent, I. Arcavi, L. Bildsten, J. Bloom, J. Brewer, T. Brown, S. B. Cenko, D. Ciardi, E. Croner, R. Dekany, G. Djorgovski, A. V. Filippenko, D. Fox, A. Gal-Yam, C. Grillmair, D. Hale, N. Hamam, D. Helfand, G. Helou, I. Hook, A. Howell, J. Jacobsen, M. Kiewe, R. Laher, A. Mahabal, S. Mattingly, J. Patterson, H. Perets, S. Perlmutter, A. Pickles, D. Poznanski, A. Rau, G. Rahmer, W. Reach, W. Rosing, M. Shara, R. Smith, D. Starr, M. Sullivan, J. Surace, R. Thomas, and V. Velur), reports the discovery of a normal type-Ia supernova (mag 18.62 +/- 0.04) in g-band images taken with the 1.2-m Oschin Schmidt telescope (+ CFH12K camera) at Palomar on Mar. 2.347 UT; the discovery image was subtracted from a reference template made from PTF images acquired on Feb. 25, 26, and 28 (which may contain some light from the rising transient). The new object is located at R.A. = 14h23m55s.82, Decl. = +35o11'05
.2 (equinox 2000.0; uncertainty < 1’'), which is 0.9 west and 2''.7 south of the core of a galaxy (listed in the Sloan Digital Sky Survey with magnitude g = 17.78 and redshift z = 0.0555). Spectra (range 330-870 nm) of 2009av, obtained on Mar. 8.388 with the 5-m Palomar Hale telescope (+ Double Beam Spectrograph), reveal a redshift that is consistent with the apparent SDSS host galaxy; the expansion velocity derived from the minimum of the Si II (rest 635.5 nm) line is about 10700 km/s. The best match of the spectra of 2009av, found with the
Superfit’’ supernova spectral-identification code (Howell et al. 2005, Ap.J. 634, 1190), is to that of SN 1994D around one week prior to maximum light.