SN 2000H: type IIb? a curious supernova

IAUC 7375 informed us about the spectra of SN 2000H obtained by ESO. They (Benetti et al.) report that they are now dominated by He I lines, and deep H-alpha absorption and tiny H-beta absorption. They conclude that it is similar to SN IIb 1993J in Messier 81, which is thought to be the core-collapse of the star who posses the tiny hydrogen-rich envelope. The evolution of spectra of SN 2000H, however, is quite different from SN 1993J, which was observed at near maximum as dominated H-alpha P-Cyg (emission and blueward absorption) profile and later resembled to that of type Ib. SN 2000H was dominated on the early phase by absorption lines around 620 nm (which should be a blend of Si II and H-alpha), 580 nm (Si II or Na I D), and 500 nm doublet (Fe II), which was quite similar with that of SNe Ic, aside from the redward steepness in 620 nm absorption (vsnet-alert 4355, vsnet-alert 4356, vsnet-alert 4357).