Vibrational structure and symmetry in 110−116Cd

Abstract

We show that a vibrational interpretation and good U(5) symmetry are maintained for the majority of low-lying normal states in 110,112,114,116Cd isotopes, consistent with the empirical data. The observed deviations from this paradigm are properly treated by an interacting boson model Hamiltonian which breaks the U(5) symmetry in selected non-yrast states, while securing a weak mixing with coexisting SO(6)-like intruder states. The results demonstrate the relevance of the U(5) partial dynamical symmetry notion to this series of isotopes