β decay of odd- A nuclei with the interacting boson-fermion model based on the Gogny energy density functional

Abstract

The low-energy excitations and $\beta$ decays of odd-A nuclei are studied within the interacting boson-fermion model (IBFM), based on the Gogny-D1M nuclear energy density functional (EDF). The constrained Hartree-Fock-Bogoliubov (HFB) approximation is employed to compute potential energy surfaces in terms of triaxial quadrupole degrees of freedom for even-even Xe and Ba nuclei in the mass $A\approx 130$ region. The mean field approximation also provides spherical single-particle energies and occupation probabilities for the neighboring odd-A nuclei. Those quantities represent a microscopic input for spectroscopic calculations in odd-A Xe and Ba, Cs and La isotopes. The Gamow-Teller (GT) and Fermi (F) transition matrix elements, needed to compute $\beta$-decay $\log{ft}$ values are obtained without any phenomenological fitting. It is shown that both the low-lying states and $\beta$ decays of the studied odd-A systems are described reasonably well within the employed theoretical framework.