Beta decay of halo nuclei

TL;DR

This paper reviews how beta decay serves as a crucial tool for understanding the structure of halo nuclei, highlighting recent experimental and theoretical advances, unique decay modes, and ongoing challenges in studying neutron-rich systems.

Contribution

It provides a comprehensive overview of beta decay processes in halo nuclei, emphasizing new experimental observations and the impact of halo structures on decay dynamics.

Findings

Beta decay reveals unique decay modes in halo nuclei.

Direct decay to continuum states observed in $^6$He and $^{11}$Li.

Challenges remain in studying multi-neutron final states.

Abstract

Beta decay is a well-established and efficient probe of nuclear structure and provides important information also for halo nuclei. Detailed decay studies of near-dripline nuclei are challenging, but are now feasible due to the technical progress during the last decades in isotope production as well as detection capabilities. The halo structure can change the dynamics of the decay process, most noticably when decays proceed directly to continuum states as seems to be the case in beta-delayed deuteron emission, a process only observed until now for the halo nuclei $^6$He and $^{11}$Li. The pronounced clustering in halo states also leaves an imprint on the decay patterns, although the isospin symmetry remains important; in several cases the isobaric analogue states of halo states have also been established. Beta-delayed particle emission channels can be expected to dominate the decays of heavier halo nuclei, if not in terms of branching ratio than certainly in terms of beta strength. A remaining challenge is to find experimental as well as theoretical tools to study the multi-neutron final states that appear for most neutron dripline nuclei.