A description of odd neutron-deficient cadmium isotopes within the rotor-plus-particle model using self-consistent core single-particle states

Abstract

Single-particle wave functions as obtained from self-consistent calculations for the core are used to calculate within the motor-plus-quasiparticle model, some spectroscopic properties of odd neutron-deficient cadmium isotopes. From constrained Hartree-Fock calculations including pairing correlations and performed with the SIII Skyrme effective force, the deformation energy curves of 98, 102, 106, 110Cd have been extracted together with the single-particle states corresponding to the equilibrium deformations. The projection of standard unified model wave functions onto eigen-functions of the core angular momentum has allowed us to introduce exactly in the core Hamiltonian the experimental level sequence of the neighbouring even isotopes. Therefore all parameters enetering the calculations are either valid for the whole chart of nuclides (effective force parameters) or unambiguously deduced from experimental data (core energies and pairing gaps). In spite of such an absence of free adjustable parameters the recently available experimental data concerning 105, 107, 109, 111Cd isotopes are correctly reproduced both for negative parity (as the expected h 11 2 decoupled band) and for positive parity states. In the 105Cd isotope, we have interpreted a set of positive parity levels as a g 7 2 decoupled band. We have also concluded that a prolated-oblate shape coexistence was absent in the low energy spectra of the isotopes considered.