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arXiv · 1209.6076

Enhanced collectivity in neutron-deficient Sn isotopes in energy functional based collective Hamiltonian

Z. P. Li·C. Y. Li·J. Xiang·J. M. Yao·J. Meng
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Abstract

The low-lying collective states in Sn isotopes are studied by a five-dimensional collective Hamiltonian with parameters determined from the triaxial relativistic mean-field calculations using the PC-PK1 energy density functional. The systematics for both the excitation energies of $2^+_1$ states and $B(E2;0^+_1\to 2^+_1)$ values are reproduced rather well, in particular, the enhanced E2 transitions in the neutron-deficient Sn isotopes with N<66. We show that the gradual degeneracy of neutron levels 1g7/2 and 2d5/2 around the Fermi surface leads to the increase of level density and consequently the enhanced paring correlations from N=66 to 58. It provokes a large quadrupole shape fluctuation around the spherical shape, and leads to an enhanced collectivity in the isotopes around N=58.

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Z. P. Li, C. Y. Li, J. Xiang, J. M. Yao, J. Meng. 2012-09-26. Enhanced collectivity in neutron-deficient Sn isotopes in energy functional based collective Hamiltonian. https://doi.org/10.1016/j.physletb.2012.09.061

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