Lifetime measurements and particle-core coupling calculations in144Sm

Abstract

Applying the generalized centroid shift method in the142Nd(α, 2n)144Sm reaction the following half-lives have been measured:T 1/2(3,376 keV)=(1.6±0.2) ns,T 1/2(3,460 keV) =(0.5±0.2) ns andT 1/2(5,150 keV)≦0.3 ns. Level energies and electromagnetic transition rates have been calculated within a particle-core coupling approach that is based on the shell model with configuration mixing. The persistence ofl-forbiddenness of M1 transitions between rather complex configurations could be confirmed.