Lifetime measurements of $^{162}\mathrm{Er}$: Evolution of collectivity in the rare-earth region
Résumé
Lifetimes of low-lying yrast states in Er162 are measured using the electronic γ-γ fast-timing technique. Excited states were populated in a Sm154(C12,4n)Er162 fusion-evaporation reaction and γ rays were detected in a combined setup of high purity germanium and LaBr3(Ce) scintillation detectors. The lifetimes of the 41+ and 61+ states are determined for the first time and the lifetimes of the 21+ and 7− states are remeasured with higher precision. Reduced transition probabilities are extracted and well reproduced by theoretical calculations in the framework of the confined β soft model and the interacting boson model.