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arXiv · 1704.07101

Shape-phase transitions in odd-mass $γ$-soft nuclei with mass $A\approx 130$

K. Nomura·T. Nikšić·D. Vretenar
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Abstract

Quantum phase transitions between competing equilibrium shapes of nuclei with an odd number of nucleons are explored using a microscopic framework of nuclear energy density functionals and a particle-boson core coupling model. The boson Hamiltonian for the even-even core nucleus, as well as the spherical single-particle energies and occupation probabilities of unpaired nucleons, are completely determined by a constrained self-consistent mean-field calculation for a specific choice of the energy density functional and pairing interaction. Only the strength parameters of the particle-core coupling have to be adjusted to reproduce a few empirical low-energy spectroscopic properties of the corresponding odd-mass system. The model is applied to the odd-A Ba, Xe, La and Cs isotopes with mass $A\approx 130$, for which the corresponding even-even Ba and Xe nuclei present a typical case of $γ$-soft nuclear potential. The theoretical results reproduce the experimental low-energy excitation spectra and electromagnetic properties, and confirm that a phase transition between nearly spherical and $γ$-soft nuclear shapes occurs also in the odd-A systems.

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K. Nomura, T. Nikšić, D. Vretenar. 2017-07-08. Shape-phase transitions in odd-mass $γ$-soft nuclei with mass $A\approx 130$. https://doi.org/10.1103/physrevc.96.014304

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