SN 2012P (A.R. 14 59 59.04, Dec. +01 53 25.1) scoperta il 22 gennaio 2012 nella galassia NGC5806 (offset 10W 1S), magnitudine 15.0, tipo Ib/c.
SN scoperta da F. Briganti con il telescopio Schmidt Cassegrain da 11" dell'Osservatorio del Col Drusciè (Cortina d'Ampezzo).
Electronic Telegram No. 2993 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 2012P IN NGC 5806 = PSN J14595904+0153251 Alessandro Dimai, Cortina d'Ampezzo, Italy, on behalf of the Italian Supernovae Search Project (ISSP), reports the discovery by Fabio Briganti (Santa Croce sull'Arno, Pisa, Italy) of an apparent supernova (mag about 15.0) on unfiltered CCD images (limiting mag about 16.5) taken with the "Maioni" 0.28-m telescope of the Osservatorio Astronomico del Col Druscie at Cortina d'Ampezzo, Italy, on Jan. 22.1556 UT. The new object is located at R.A. = 14h59m59s.12, Decl. = +1d53'24".4 (equinox 2000.0), which is 10" west and 1" south of the nucleus of NGC 5806. Nothing is visible at this position on Palomar Sky Survey infrared, red, and blue plates. The discovery image is posted at website URL http://tinyurl.com/7lzoeyv. The variable was designated PSN J14595904+0153251 when it was posted at the Central Bureau's TOCP webpage and is here designated SN 2012P based on the spectroscopic confirmation reported below. Additional CCD magnitudes for 2012P (unfiltered unless noted otherwise): 2011 Dec. 7, [18.0 (ISSP); 2012 Jan. 23.227, 15.2 (Briganti); 23.549, 16.3 (Joseph Brimacombe, Cairns, Australia; remotely using a 51-cm RCOS telescope + STL11K camera + luminance filter at the New Mexico Skies Observatory near Mayhill, NM, U.S.A.; position end figures 59s.09, 24".1; image posted at URL http://www.flickr.com/photos/43846774@N02/6752536997/). The type-II supernova 2004dg also appeared in NGC 5806 (cf. IAUC 8375). L. Borsato and V. Nascimbeni, Dipartimento di Fisica e Astronomia, Universita di Padova; and S. Benetti, A. Pastorello, S. Valenti, L. Tomasella, E. Cappellaro, P. Ochner, and M. Turatto, Osservatorio Astronomico di Padova, Istituto Nazionale di Astrofisica, report that a spectrum (range 360-810 nm; resolution 2.2 nm) of PSN J14595904+0153251 = SN 2012P was obtained on Jan. 23.17 UT with the Ekar-Copernico 1.82-m telescope (+ AFOSC). Using a library of supernova spectra via GELATO (Harutyunyan et al. 2008, A.Ap. 488, 383; available via https://gelato.tng.iac.es/login.cgi), they found a best match with typical type-Ib/c supernovae soon after maximum if a redshift of z = 0.004533 (Falco et al. 1999, PASP 111, 438; via NED) is assumed. From the minimum of a deep-intense absorption measured at 627.6 nm, an expansion velocity of about 5100 km/s is deduced for the ejecta if identified with Si II 635.5-nm (but an expansion velocity of about 14400 km/s if identified with H-alpha). NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2012 CBAT 2012 January 25 (CBET 2993) Daniel W. E. Green