Lifetime of a new high-spin isomer in 150 Dy

Abstract

A new high-spin isomer in 150Dy has been observed at an excitation energy of 10.3 MeV by combining the inverse-kinematic reaction induced by a pulsed beam of 132Xe and the $\gamma$ -ray recoil-shadow technique. The half-life of this isomeric state has been determined to be $T_{1/2} = 1.6 \pm 0.6$ ns using the conventional centroid-shift method with the 141Pr(16O, p6n)150Dy reaction at 165 MeV. The mechanism producing high-spin isomers in N = 83,84 isotones is qualitatively discussed in terms of the difference of the neutron particle-hole configuration between the high-spin isomer and the lower-lying state.