2012CBET.3190....2M

N. Morrell, Las Campanas Observatory, Carnegie Supernova Project; J.-R. Gauthier, Cahill Center for Astronomy and Astrophysics, California Institute of Technology; and M. Rauch, Carnegie Observatories, report that on July 22.4 UT they obtained an optical spectrogram (range 360-940 nm) of PSN J21491632-6042426 = 2012du with the 6.5-m Magellan II (Clay) telescope (+ LDSS3) at Las Campanas Observatory. Analysis of the data reveals that 2012du is a type-II supernova. Adopting for NGC 7125 the NED recession velocity of 3148 km/s (Schweizer 1987, Ap.J. Suppl. 64, 411), in coincidence with H-alpha nebular emission from a surrounding H II region that appears to be present in the supernova spectrum, the minimum of the H-beta absorption appears to be blueshifted by 6000 km/s. Unresolved Na I absorption at the redshift of the host galaxy is present with an equivalent width of 0.057 nm. Comparison with a library of supernova spectra via the Supernova Identification tool (SNID, Blondin and Tonry 2007, Ap.J. 666, 1024) provides excellent matches with a number of type II-p supernovae at 2-3 weeks after explosion.