REFLECTION ASYMMETRIC SHAPE IN 221Ra

Abstract

Mass separated sources of 225Th were used to study the level structure of 221Ra following alpha decay. Fluorination techniques were used to obtain the selectivity in atomic number. The low lying levels in 221Ra are interpreted in terms of K=5/2± and 3/2± parity doublet bands which occur naturally from reflection asymmetric models. The anomalous spin sequences in the K= 3/2± bands of 221Ra are interpreted in terms of their Coriolis coupling with K=1/2± bands with large decoupling parameters. The low-lying parity doublet bands in 221Ra, 223Ra and 225Ra, and particularly the Coriolis coupling of their K=3/2± bands, are compared and contrasted.