2012CBET.3107....2M

G. H. Marion and R. J. Foley, Harvard-Smithsonian Center for Astrophysics (CfA), on behalf of the CfA Supernova Group, report that a spectrum (range 340-740 nm) of 2012cd was obtained on May 12 UT by M. Calkins with the F. L. Whipple Observatory 1.5-m telescope (+ FAST). Cross-correlation with a library of supernova spectra using the "Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) shows that 2012cd is a type-IIb supernova near maximum light. A prominent P-Cyg feature from H-alpha is present, as well as absorption features from other Balmer-series lines and absorption from multiple lines of He I. The velocity of H, measured at the absorption minima, is about 9000 km/s. The He I velocity is about 6000 km/s. Good fits are found to several templates of SN 1993J a few days before maximum brightness.