Spectroscopy and lifetime measurements inGe66,Se69, and

Abstract

Lifetimes of low-lying excited states have been measured in 66 Ge, 69 Se and 65 Ga using a γ-ray lineshape method. The results confirm the previously reported 7 − 1 state lifetime in 66 Ge. The lifetime of the yrast 5/2 − state in 65 Ga is measured for the first time. Lifetime measurements of two excited 3/2 − states in 69 Se are also reported. Two previously unobserved γ rays have been identified in 69 Se. γ-γ coincidence measurements have been used to place one of these in the level scheme. 69 Se excited state populations are compared to shell-model calculations using the GXPF1A interaction in the fp model space. Theoretical spectroscopic factors to excited states in 69 Se have identified three candidate levels for the origin of one of the new transitions.