Vibrational structure and symmetry in ${}^{110-116}$Cd

Abstract

We show that a vibrational interpretation and good U(5) symmetry are maintained for the majority of low-lying normal states in ${}^{110,112,114,116}$Cd 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.

9 pages, 2 figures, 4 Tables, Proceedings of the Zakopane Conference on Nuclear Physics "Extremes of the Nuclear Landscape", Zakopane, Poland, August 25 - September 1, 2024