Two- and three-cluster decays of light nuclei within a hyperspherical harmonics approach

We consider a set of three-cluster systems (He-4, Li-7, Be-7, Be-8, Be-10) within a microscopic model which involves hyperspherical harmonics to represent intercluster motion. We selected three-cluster systems which have at least one binary channel. Our aim is to study whether hyperspherical harmonics are able, and under what conditions, to describe two-body channel(s) (nondemocratic motion) or if they are suitable for describing the three-cluster continuum only (democratic motion). It is demonstrated that a rather restricted number of hyperspherical harmonics allows us to describe bound states and scattering states in the two-body continuum for a three-cluster system.