Structure of Exotic Three-Body Systems

Abstract

The classification of large halos formed by two identical particles and a core is systematically addressed according to interparticle distances. The root-mean-square distances between the constituents are described by universal scaling functions obtained from a renormalized zero-range model. Applications for halo nuclei, 11 Li and 14 Be, and for atomic 4 He 3 are briefly discussed. The generalization to four-body systems is proposed. *

Few-body quark dynamics for doubly heavy baryons and tetraquarks

“…This strategy is of course fully justified for the deuterium atom considered as a pne − system, as the internuclear motion is not significantly modified by the electron. On the other hand, this approach ruins some subtle collective binding, for instance, that of Borromean states [15]. Also, one cannot see either how H − (pe − e − ) could become bound in this approach, or the hydrogen molecule be described as a "diproton" linked to a "dielectron"!…”

Hall–Post inequalities: Review and application to molecules and tetraquarks

“…For non-identical particles, the inequality involves several couplings. If, for instance, ones considers a system (a, a, b) with two couplings normalized such that g ij is the coupling threshold for binding the {i, j} pair, one can distinguish two domains in the {g aa , g ab } plane, one near g aa = g ab = 0 without 3-body binding and another one with 3-body binding and four regions (see, e.g., [36]):…”

Halos and related structures

“…However, the physical hypertriton has a bound subsystem (the deuteron) and is further away. That radii increase (for a given three-body binding energy) as more and more subsystems become bound is likely to be a general effect [29]. The arrows indicate the positions where a two-body subsystem goes from being bound to unbound.…”