Supernova 2013cc in NGC 1961 = Psn J05415876+6921409

Koichi Itagaki, Yamagata, Japan, reports his discovery of an apparent supernova (mag 17.0) on unfiltered CCD images (limiting mag 19.5) taken on Apr. 28.468 UT with a 0.60-m f/5.7 reflector. The new object is located at R.A. = 5h41m58s.76, Decl. = +69d21'40".9 (equinox 2000.0; UCAC3 reference stars), which is 31" west and 62" south of the center of the galaxy NGC 1961 (whose measured center has position end figures 42m04s.62, 22'43".2). Itagaki has posted his images at URL http://www.k-itagaki.jp/images/ngc1961.jpg. The variable was designated PSN J05415876+6921409 when it was posted at the Central Bureau's TOCP webpage and is here designated SN 2013cc based on the spectroscopic confirmation reported below. Additional CCD magnitudes for 2013cc: 2006 Nov. 25.603, [19.5 (Itagaki); 2013 Apr. 13.464, [19.0 (Itagaki); 28.532, 17.2 (Toshihide Noguchi, Katori, Chiba-ken, Japan; 0.23-m f/6.3 reflector + BITRAN BT-11E camera; position end figures 58s.69, 41".2; UCAC3 reference stars; offset 30" west, 62" south; limiting mag 18.0; image posted at website URL http://park8.wakwak.com/~ngc/images/PSNinNGC1961.jpg; communicated by S. Nakano); 29.140, 16.6 (L. Elenin, Lyubertsy, Russia; and I. Molotov, Moscow, Russia; remotely taken with a 0.45-m f/2.8 telescope at the ISON-NM Observatory near Mayhill, NM, USA; position end figures 58s.73 +/- 0".09, 40".9 +/- 0".07; limiting mag about 20.3; image posted at website URL http://spaceobs.org/images/TOCP/PSNJ05415876+6921409-20130429.png); 29.161, V = 16.64 and I_c = 16.35 (Seiichiro Kiyota, Tsukuba, Japan; 0.43-m f/6.8 astrograph + FLI-PL6303E camera of the iTelescope.net near Mayhill); 29.259, 16.5 (Joseph Brimacombe, Cairns, Australia; remotely with a 51-cm RCOS telescope + STL11K camera + luminance filter at the New Mexico Skies observatory near Mayhill; mag 16.4 using a infrared filter with bandpass > 700 nm; position end figures 58s.68, 41".2; image posted at website URL http://www.flickr.com/photos/43846774@N02/8698583180/). P. Ochner, L. Tomasella, A. Pastorello, S. Benetti, E. Cappellaro, and M. Turatto, Osservatorio Astronomico di Padova, Istituto Nazionale di Astrofisica, report that an optical spectrogram (range 340-790 nm; resolution 0.9 nm), obtained on May 4.86 UT with the Asiago 1.22-m Galileo Telescope (+ Boller & Chivens spectrograph), shows that PSN J05415876+6921409 = SN 2013cc is a young type-II supernova. The spectrum shows a blue continuum with shallow P-Cyg lines of H and He I. Assuming a recessional velocity of 3934 km/s for the host galaxy, NGC 1961 (Strauss et al. 1992, Ap.J. Suppl. 83, 29; Haan et al. 2008, A.J. 135, 232), an expansion velocity of about 10500 km/s is derived from the position of the H-beta minimum. The best match is found with the spectrum of SN 2006bp around maximum light (Quimby et al. 2007, Ap.J. 666, 1093). The Asiago classification spectra are posted at website URL http://graspa.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).