Electronic Telegram No. 3337 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 2012hn IN NGC 2272 = PSN J06424255-2726498 S. Howerton, Arkansas City, KS, U.S.A.; A. J. Drake, S. G. Djorgovski, A. Mahabal, M. J. Graham, and R. Williams, California Institute of Technology; J. L. Prieto, Princeton University; M. Catelan, Pontificia Universidad Catolica de Chile; R. H. McNaught, Australian National University; and E. C. Beshore, S. M. Larson, and E. Christensen, Lunar and Planetary Laboratory, University of Arizona, report the discovery of an apparent supernova in public images from the Siding Spring Survey (SSS): SN 2012 UT R.A. (2000.0) Decl. Mag. Offset 2012hn Apr. 4.41 6 42 42.55 -27 26 49.8 16.5 16".6 E, 44".4 N The variable was designated PSN J06424255-2726498 when it was posted at the Central Bureau's TOCP webpage and is here designated SN 2012hn based on the spectroscopic confirmation reported below. Additional magnitudes for 2012hn: 2011 Apr. 7.46 UT, [19.5 (SSS); 2012 Apr. 16.127, 18.6 (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 42s.56, 50".3; image posted at the following website URL: http://www.flickr.com/photos/43846774@N02/7083122477/); May 16.42, 17.3 (SSS). S. Benitez-Herrera and S. Taubenberger, Max-Planck-Institut fuer Astrophysik; and S. Valenti, S. Benetti, and A. Pastorello, Istituto Nazionale di Astrofisica, Osservatorio Astronomico di Padova, on behalf of a larger collaboration, report that a spectrogram of PSN J06424255-2726498 = SN 2012hn, obtained on Apr. 14.02 UT with the European Southern Observatory's New Technology Telescope (+ EFOSC2; range 365-930 nm; resolution 1.8 nm), shows it to be a peculiar type-Ic supernova. The best matches to this spectrum found by GELATO (Harutyunyan et al. 2008, A.Ap. 488, 383; available at website URL https://gelato.tng.iac.es/login.cgi) suggest that 2012hn was then a few weeks after maximum light. There are prominent O I and Ca II lines, but also several unidentified features. There is no clear evidence for the presence of H or He lines. The redshift of the host galaxy, NGC 2272, is z = 0.007 (Wegner et al. 2003, A.J. 126, 2268; via NED). S. Valenti, University of California at Santa Barbara and Las Cumbres Observatory Global Telescope; S. Benitez-Herrera and S. Taubenberger, Max-Planck-Institute fuer Astrophysik, Garching; A. Pastorello and S. Benetti, Istituto Nazionale di Astrofisica, Padova; S. J. Smartt, D. Young, and K. Smith, Queen's University, Belfast; M. Sullivan, University of Southampton; and I. Arcavi, A. Gal-Yam, and O. Yaron, Weizmann Institute of Science, on behalf of the PESSTO collaboration (see Valenti et al., posted at website URL http://www.astronomerstelegram.org/?read=4037), report that a spectrogram of PSN J06424255-2726498 = SN 2012hn, obtained on Apr. 14.02 UT with the European Southern Observatory's New Technology Telescope (+ EFOSC2; range 365-930 nm; resolution 1.8 nm), shows it to be a faint, peculiar type-I supernova (see Benitez-Herrera et al., at URL http://www.astronomerstelegram.org/?read=4047). Subsequent spectroscopic monitoring (Apr. 20, 22, and 29, May 11 and 18, and Sept. 13 and 14) confirms the initial classification. Lines of Ti II, Ca II, and Fe II are clearly visible, while H and He I have never been detected. In addition, the faint peak absolute magnitude supports the idea that 2012hn is photometrically similar to the peculiar, stripped-envelope supernova 2005E (Peretz et al. 2010, Nature 465, 322). NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2012 CBAT 2012 December 12 (CBET 3337) Daniel W. E. Green