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arXiv · 1905.04633

Valence Neutron-Proton Orientation in Atomic Nuclei

J. G. Wang·M. L. Liu·C. M. Petrache·K. K. Zheng·X. H. Zhou·Y. H. Zhang
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Abstract

It is shown that the renormalized nuclear deformations in different mass regions can be globally scaled by two probability partition factors of Boltzmann-like distribution, which are derived from the competing valence $np$ and like-nucleon interactions. The partition factors are simply related to the probabilities of anti-parallel and fully-aligned orientations of the angular momenta of the neutrons and protons in the valence $np$ pairs, responsible for spherical- and deformed-shape phases, respectively. The partition factors derived from the renormalized deformations are also present in the new scaling law for the energies of the first $2^+$ states. A striking concordance between the distributions of the renormalized deformations and of the newly introduced parameter for the energies of the first $2^+$ states over the extended mass region from Ge to Cf is achieved, giving strong support to the existence of two phases: anti-aligned and fully-aligned subsets of $np$ pairs.

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J. G. Wang, M. L. Liu, C. M. Petrache, K. K. Zheng, X. H. Zhou, Y. H. Zhang. 2019-05-12. Valence Neutron-Proton Orientation in Atomic Nuclei. https://arxiv.org/abs/1905.04633

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