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arXiv · 1109.5754

Robust Regularity in \gamma-Soft Nuclei and its Microscopic Realization

K. Nomura·N. Shimizu·D. Vretenar·T. Niksic·T. Otsuka
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Abstract

\gamma-softness in atomic nuclei is investigated in the framework of energy density functionals. By mapping constrained microscopic energy surfaces for a set of representative non-axial medium-heavy and heavy nuclei to a Hamiltonian of the proton-neutron interacting boson model (IBM-2) containing up to three-body interactions, low-lying collective spectra and transition rates are calculated. Observables are analyzed that distinguish between the two limiting geometrical pictures of non-axial nuclei: the rigid-triaxial rotor and the \gamma-unstable rotor. It is shown that neither of these pictures is realized in actual nuclei, and that a microscopic description leads to results that are almost exactly in between the two geometrical limits. This finding points to the optimal choice of the IBM Hamiltonian for \gamma-soft nuclei.

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K. Nomura, N. Shimizu, D. Vretenar, T. Niksic, T. Otsuka. 2011-09-27. Robust Regularity in \gamma-Soft Nuclei and its Microscopic Realization. https://doi.org/10.1103/physrevlett.108.132501

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