Change of shell structure and magnetic moments of odd-N deformed nuclei towards neutron drip line

TL;DR

This paper investigates how neutron shell structures change near the neutron drip line, leading to nuclear deformation and altered magnetic moments, especially in nuclei around traditional magic numbers, using theoretical models.

Contribution

It demonstrates the impact of weak binding on shell structure and deformation in neutron-rich nuclei, providing a theoretical framework for understanding these phenomena.

Findings

Shell-structure changes induce deformation in nuclei near magic numbers.

Magnetic moments of weakly-bound odd-N nuclei are calculated and analyzed.

Deformation explains properties of nuclei in the island of inversion.

Abstract

Examples of the change of neutron shell-structure in both weakly-bound and resonant neutron one-particle levels in nuclei towards the neutron drip line are exhibited. It is shown that the shell-structure change due to the weak binding may lead to the deformation of those nuclei with the neutron numbers $N \approx$ 8, 20, 28 and 40, which are known to be magic numbers in stable nuclei. Nuclei in the "island of inversion" are most easily and in a simple manner understood in terms of deformation. As an example of spectroscopic properties other than single-particle energies, magnetic moments of some weakly-bound possibly deformed odd-N nuclei with neutron numbers close to those traditional magic numbers are given, which are calculated using the wave function of the last odd particle in deformed Woods-Saxon potentials.