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arXiv · 1003.4109

Microscopic Description of Spherical to Gamma-Soft Shape Transitions in Ba and Xe Nuclei

Z. P. Li·T. Niksic·D. Vretenar·J. Meng
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Abstract

The rapid transition between spherical and $γ$-soft shapes in Ba and Xe nuclei in the mass region $A \geq 130$ is analyzed using excitation spectra and collective wave functions obtained by diagonalization of a five-dimensional Hamiltonian for quadrupole vibrational and rotational degrees of freedom, with parameters determined by constrained self-consistent relativistic mean-field calculations for triaxial shapes. The results reproduce the characteristic evolution of excitation spectra and E2 transition probabilities and, in general, a good agreement with available data is obtained. The calculated spectra display fingerprints of a second-order shape phase transition that can approximately be described by analytic solutions corresponding to the E(5) dynamical symmetry.

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Z. P. Li, T. Niksic, D. Vretenar, J. Meng. 2010-03-22. Microscopic Description of Spherical to Gamma-Soft Shape Transitions in Ba and Xe Nuclei. https://doi.org/10.1103/physrevc.81.034316

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