Shape evolution and the role of intruder configurations in Hg isotopes within the interacting boson model based on a Gogny energy density functional

Abstract

The interacting boson model with configuration mixing, with parameters derived from the self-consistent mean-field calculation employing the microscopic Gogny energy density functional, is applied to the systematic analysis of the low-lying structure in Hg isotopes. Excitation energies, electromagnetic transition rates, deformation properties, and ground-state properties of the $^{172-204}$Hg nuclei are obtained by mapping the microscopic deformation energy surface onto the equivalent IBM Hamiltonian in the boson condensate. These results point to the overall systematic trend of the transition from the near spherical vibrational state in lower-mass Hg nuclei close to $^{172}$Hg, onset of intruder prolate configuration as well as the manifest prolate-oblate shape coexistence around the mid-shell nucleus $^{184}$Hg, weakly oblate deformed structure beyond $^{190}$Hg up to the spherical vibrational structure toward the near semi-magic nucleus $^{204}$Hg, as observed experimentally. The quality of the present method in the description of the complex shape dynamics in Hg isotopes is examined.