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arXiv · 1411.3821

Covariant density functional analysis of shape evolution in $N =40$ isotones

Z. H. Wang·J. Xiang·W. H. Long·Z. P. Li
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Abstract

The structure of low-lying excitation states of even-even $N=40$ isotones is studied using a five-dimensional collective Hamiltonian with the collective parameters determined from the relativistic mean-field plus BCS method with the PC-PK1 functional in the particle-hole channel and a separable paring force in the particle-particle channel. The theoretical calculations can reproduce not only the systematics of the low-lying states along the isotonic chain but also the detailed structure of the spectroscopy in a single nucleus. We find a picture of spherical-oblate-prolate shape transition along the isotonic chain of $N=40$ by analyzing the potential energy surfaces. The coexistence of low-lying excited $0^+$ states has also been shown to be a common feature in neutron-deficient $N=40$ isotones.

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Z. H. Wang, J. Xiang, W. H. Long, Z. P. Li. 2014-11-14. Covariant density functional analysis of shape evolution in $N =40$ isotones. https://doi.org/10.1088/0954-3899%2F42%2F4%2F045108

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