The neutron-rich edge of the nuclear landscape: Experiment and theory

In this review, we describe the experimental facilities and methods which make it possible to produce and measure the properties of the extreme neutron-rich nuclei. We then develop the theoretical framework that predicts and explains these properties; the shell-model approach with large-scale configuration interaction (mixing) SM-CI, with special emphasis in the competition between the spherical mean field and the nuclear correlations (mainly pairing and quadrupole-quadrupole). The SU(3) related symmetry properties of the latter are treated in detail as they will show to be of great heuristic value. We explore the Islands of Inversion (IoI) at N = 20 and N = 28. We make a side excursion into the heavier Calcium and Potassium isotopes, to discuss current issues on shell evolution and new magic numbers far from stability. We revisit the N = 40 Island of Inversion and extrapolate the successful predictions of the LNPS model to Ca-60. We discuss the doubly magic nucleus Ni-78, its shape coexistence and the prospect of a new IoI at N = 50 below Z = 28. Finally, we examine the behaviour of the N = 70 and N = 82 neutron closures as the neutron drip line is approached. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

This review discusses the experimental facilities and methods for studying extreme neutron-rich nuclei, as well as the theoretical framework that predicts and explains their properties. Emphasis is placed on the shell-model approach with large-scale configuration interaction, the competition between the spherical mean field and nuclear correlations, and the SU(3) related symmetry properties. The article also explores Islands of Inversion, shell evolution, new magic numbers, and behaviors of neutron closures near the neutron drip line.