2010CBET.2315....1M

N. Morrell and M. Phillips, on behalf of the Carnegie Supernova Project, report that a spectrum (range 380-940 nm) of 2010cl (cf. CBET 2266) was obtained on May 21.0 UT with the 6.5-m Magellan II Clay telescope (+ LDSS3) at Las Campanas Observatory, which reveals that this is a type-II supernova. Cross-correlation with a library of supernova spectra using the Supernova Identification Tool of Blondin and Tonry (2007, Ap.J. 666, 1024) yields good matches with a number of type-II-P events at 1 month or more after explosion, with 2006bp at +34 days being the best comparison. A radial velocity of 2602 km/s is measured from narrow H II region emission at the position of the supernova. The minimum of the H-alpha absorption is found to be blueshifted with respect to this velocity by roughly 7400 km/s.