SN 2013ff (A.R., 09 13 38.88 Dec. +76 28 10.8), scoperta il 31 agosto 2013 nella galassia ngc 2748 (offset 18W 20S), magnitudine 16.0, tipo: Ic
SN individuata da Raffaele Belligoli e Flavio Castellanii con il telescopio Newton da 40cm dell'Osservatorio di Monte Baldo (Verona).
Electronic Telegram No. 3647 - 3656 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: Questo indirizzo e-mail è protetto dallo spam bot. Abilita Javascript per vederlo. (alternate Questo indirizzo e-mail è protetto dallo spam bot. Abilita Javascript per vederlo. ) URL http://www.cbat.eps.harvard.edu/index.html Prepared using the Tamkin Foundation Computer Network SUPERNOVA 2013ff IN NGC 2748 = PSN J09133888+7628108 Raffaele Belligoli and Flavio Castellani report the discovery of an apparent supernova (mag 16.0) on two unfiltered CCD images taken with a 0.4-m reflector at Ferrara di Monte Baldo, Verona, Italy, on Aug. 31.94 and 31.94 UT. The new object is located at R.A. = 9h13m38s.88, Decl. = +76d28'10".8 (equinox 2000.0), which is 19" west and 21" south of the center of NGC 2748. The discovery and reference images were posted at the following website URL: http://www.flickr.com/photos/27458003@N05/9645256677/. The variable was designated PSN J09133888+7628108 when it was posted at the Central Bureau's TOCP webpage and is here designated SN 2013ff based on the spectroscopic confirmation reported below. Additional CCD magnitudes for 2013ff: Sept. 1.804, 15.9 (Giancarlo Cortini, Predappio, Italy; independent discovery; position end figures 38s.82, 10".7; offset 19" west, 21" north; no other information provided); 2.168, 16.1 (J. Brimacombe, Cairns, Australia; remotely with a 51-cm telescope + luminance filter located at the New Mexico Skies observatory near Mayhill, NM, U.S.A.; position end figures 39s.01, 10".5; image posted at URL http://www.flickr.com/photos/43846774@N02/9657496645/); 4.054, B = 16.33, V = 15.52, B-V = +0.81 (Belligoli and Castellani); 4.146, 15.2 (Federica Luppi and Luca Buzzi, Varese, Italy, 0.36-m f/7.1 reflector; position end figures 38s.86, 10".4; reference stars from PPMXL catalogue; image posted at URL http://www.astrogeo.va.it/pub/TOCP/PSN_N2748.jpg); 6.959, B = 16.28, V = 15.43, B-V = +0.84 (Belligoli and Castellani). S. Zaggia, M. Barbieri, A. Silvestri, V. Ronzani, S. Benetti, A. Pastorello, E. Cappellaro, L. Tomasella, P. Ochner, and M. Turatto, Osservatorio Astronomico di Padova, Istituto Nazionale di Astrofisica; and S. Valenti, Las Cumbres Observatory Global Telescope and University of California at Santa Barbara, report that an optical spectrogram (range 340-820 nm; resolution 1.3 nm) of PSN J09133888+7628108 = SN 2013ff, obtained on Sept. 2.95 UT with the Asiago 1.82-m Copernico Telescope (+ AFOSC), shows it to be a type-Ic supernova. Adopting for the host galaxy (NGC 2748) a recessional velocity of 1476 km/s (Kamphuis et al. 1996, A.Ap. Supple. 116, 15; via NED), a best fit is found with type-Ic supernovae around maximum light. 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 September 9 (CBET 3647) Daniel W. E. Green