Description of neutron-rich odd-mass krypton isotopes within the interacting boson-fermion model based on the Gogny energy density functional

Abstract

The low‑lying structure of neutron‑rich odd‑mass Kr isotopes (⁸⁷–⁹⁵Kr) is studied within the interacting boson‑fermion model (IBFM) based on the Gogny‑D1M energy density functional. The (β, γ)-deformation energy surfaces, spherical single-particle energies, and occupation probabilities of the odd-mass systems are computed via the constrained Hartree‑Fock‑Bogoliubov approximation. These microscopic inputs determine most of the IBFM Hamiltonian parameters; the remaining coupling constants are tailored to experimental spectra for each studied isotope. The model predicts a gradual structural evolution of collectivity matching trends observed in neighboring even–even Kr isotopes.