Inference of weak nuclear collectivity from atomic masses

TL;DR

This paper demonstrates that atomic masses can be used to infer weak nuclear collectivity in certain nuclei, linking macroscopic mass data to microscopic nuclear structure properties.

Contribution

It introduces a method to predict nuclear collectivity, specifically E2 transition strengths, from pairing gaps derived from atomic mass measurements.

Findings

Excellent agreement with Ni isotope data.

Supported trend in Sn isotopes from recent experiments.

Highlights atomic masses as a tool for nuclear-structure inference.

Abstract

I explore weakly-collective singly-closed shell nuclei with high-j shells where active valence neutrons and particle-particle correlations may be the dominant collective degree of freedom. The combination of large and close-lying proton and neutron pairing gaps extracted from experimental masses seems to charaterize the origin of the weak collectivity observed in Ni and Sn superfluids with $N\approx Z$. The trend of $E2$ transition strengths, i.e., $B(E2; 2^+_1\rightarrow 0^+_1)$ values, in these nuclei is predicted from proton and neutron pairing-gap information. The agreement with the Ni isotopes is excellent and recent experimental results support the trend in the Sn isotopes. This work emphasizes the importance of atomic masses in elucidating nuclear-structure properties. In particular, it indicates that many-body microscopic properties such as nuclear collectivity could be directly inferred from more macroscopic average properties such as atomic masses.