Few-body aspects of Borromean halo nuclei

Abstract

Nuclei that exhibit pronounced halo structures are currently being explored in secondary beam experiments. Although 11Li is the most famous example of a system with a halo of two loosely bound valence neutrons, 6He shares many of the same properties. Both are what we refer to as Borromean, i.e. while they are bound (only one bound state) they have, considered as three-body systems, no bound states in the binary subsystems. We argue that a three-body description is the natural one for central properties of such exotic loosely bound nuclei. Using 6He as a benchmark system, we give a discussion of characteristic features by comparing recent calculations and experiments.