Low-energy properties of three resonantly interacting particles

The scattering processes and bound states of three resonantly interacting particles are treated. It is shown that their properties are independent of the kind of the two-particle forces and are determined only by the fact of existence of resonances. The resonances generate a long-range interaction between three particles. It is found that the physical characteristics of three resonantly interacting particles show the scaling behaviour. Explicit expressions are derived for the particle-pair scattering length, for the cross section of the particle-pair scattering at and above the three-particle disintegration threshold, for the triple-collision amplitude at zero energy. The properties of two and three resonantly interacting particles are compared