Electronic Telegram No. 3624 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 2013et IN UGC 1723 = PSN J02141705+0735118 [Editor's note: this text replaces that on CBET 3623 (offset)] F. Ciabattari, E. Mazzoni, and S. Donati, Borgo a Mozzano, Italy, report their discovery of an apparent supernova (mag 18.4) on unfiltered CCD images (limiting magnitude 19.5) obtained on Aug. 2.08 and 3.04 UT with a 0.5-m Newtonian telescope in the course of the Italian Supernovae Search Project. The new object is located at R.A. = 2h14m17s.05, Decl. = +7d35'11".8 (equinox 2000.0; astrometry with respect to UCAC-2 stars), which is 4" west and 6" south of the center of the galaxy UGC 1723. Nothing is visible at this position on the digitized plates of the Palomar Sky Survey from 1990 Oct. 22 (F plate; limiting magnitude 20.3) and 1992 Sept. 7 (J plate; limiting mag 20.3). The variable was designated PSN J02141705+0735118 when it was posted at the Central Bureau's TOCP webpage and is here designated SN 2013et based on the spectroscopic confirmation reported below. Additional CCD magnitudes for 2013et: Aug. 3.418, 17.4 (L. Elenin, Lyubertsy, Russia, and I. Molotov, Moscow; images remotely taken with a 0.45-m f/2.8 telescope at the ISON-NM Observatory near Mayhill, NM, USA; limiting mag about 19.6; position end figures 17s.03 +/- 0".13, 12".3 +/- 0".13; UCAC-4 reference stars; image posted at http://spaceobs.org/images/TOCP/PSNJ02141705+0735118-20130803.png); 5.074, R = 16.7 (Xavier Bros, Ager, Spain; 0.35-m f/4.6 telescope; position end figures 17s.17, 17".1; UCAC2 reference stars; image posted at website URL http://www.anysllum.com/PSN_UGC1723.jpg); 5.796, 19.4 (Joseph Brimacombe, Cairns, Australia; 43-cm telescope + infrared filter; bandpass > 700 nm; position end figures 17s.04, 12".1; image posted at website URL http://www.flickr.com/photos/43846774@N02/9447719247/). L. Tomasella, P. Ochner, A. Pastorello, S. Benetti, E. Cappellaro, and M. Turatto, Osservatorio Astronomico di Padova, Istituto Nazionale di Astrofisica, report that a noisy optical spectrogram (range 340-820 nm; resolution 1.3 nm) of PSN J02141705+0735118 = SN 2013et, obtained on Aug. 8.05 UT with the Asiago 1.82-m Copernico Telescope (+ AFOSC), shows that it is a normal type-Ia supernova. Adopting for the host galaxy (UGC 1723) the redshift z = 0.057 (Springob et al. 2005, Ap.J. Suppl. 160, 149; via NED), a good match is found with the type-Ia supernova 1989B (Barbon et al. 1990, A.Ap. 237, 79) around one week after the B-band maximum. The Asiago classification spectra are posted at website URL "http://sngroup.oapd.inaf.it"; classification was made via GELATO (Harutyunyan et al. 2008, A.Ap. 488, 383) and SNID (Blondin and Tonry 2007, Ap.J. 666, 1024). NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2013 CBAT 2013 August 12 (CBET 3624) Daniel W. E. Green