Regularity and chaos in the nuclear masses

TL;DR

This paper reviews how quantum shell effects in atomic nuclei relate to regular or chaotic nucleonic motion, using theoretical models and experimental data to analyze their impact on nuclear masses.

Contribution

It provides a comprehensive review of recent advances linking shell effects, quantum chaos, and nuclear mass fluctuations through theoretical and experimental analysis.

Findings

Evidence of regular and chaotic nucleonic motion in nuclear mass data

Shell effects significantly influence nuclear mass fluctuations

Theoretical models align with experimental observations of quantum chaos in nuclei

Abstract

Shell effects in atomic nuclei are a quantum mechanical manifestation of the single--particle motion of the nucleons. They are directly related to the structure and fluctuations of the single--particle spectrum. Our understanding of these fluctuations and of their connections with the regular or chaotic nature of the nucleonic motion has greatly increased in the last decades. In the first part of these lectures these advances, based on random matrix theories and semiclassical methods, are briefly reviewed. Their consequences on the thermodynamic properties of Fermi gases and, in particular, on the masses of atomic nuclei are then presented. The structure and importance of shell effects in the nuclear masses with regular and chaotic nucleonic motion are analyzed theoretically, and the results are compared to experimental data. We clearly display experimental evidence of both types of motion