Abstract
From gamma - gamma , X-X, X- gamma , and gamma - gamma - gamma coincidence studies of spontaneous fission of 252Cf, 160Sm levels were identified along with new high spin states in 156,158Sm. New bands, beginning at 5- in 156,158Sm are assigned a two-neutron configuration (5/2+(642) 5/2-(523))5-. The J1 and J2 values for the yrast bands increase smoothly with spin and neutron number and the differences in these values for corresponding transitions in neighbouring isotopes are reasonably constant.