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arXiv · 1710.03908

Shape transitions in odd-mass $γ$-soft nuclei within the interacting boson-fermion model based on the Gogny energy density functional

K. Nomura·R Rodríguez-Guzmán·L. M. Robledo
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Abstract

The interacting boson-fermion model (IBFM), with parameters determined from the microscopic Hartree-Fock-Bogoliubov (HFB) approximation, based on the parametrization D1M of the Gogny energy density functional (EDF), is employed to study the structural evolution in odd-mass $γ$-soft nuclei. The deformation energy surfaces of even-even nuclei, single-particle energies and occupation probabilities of the corresponding odd-mass systems have been obtained within the constrained HFB approach. Those building blocks are then used as a microscopic input to build the IBFM Hamiltonian. The coupling constants of the boson-fermion interaction terms are taken as free parameters, fitted to reproduce experimental low-lying spectra. The diagonalization of the IBFM Hamiltonian provides the spectroscopic properties for the studied odd-mass nuclei. The procedure has been applied to compute low-energy excitation spectra and electromagnetic transition rates, in the case of the $γ$-soft odd-mass systems $^{129-137}$Ba, $^{127-135}$Xe, $^{129-137}$La and $^{127-135}$Cs. The calculations provide a reasonable agreement with the available experimental data and agree well with previous results based on the relativistic mean-field approximation.

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K. Nomura, R Rodríguez-Guzmán, L. M. Robledo. 2017-12-21. Shape transitions in odd-mass $γ$-soft nuclei within the interacting boson-fermion model based on the Gogny energy density functional. https://doi.org/10.1103/physrevc.96.064316

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