Three-Nucleon Interactions in Yukawa Theory

Abstract

The method of Salpeter and Bethe is applied to the three-nucleon bound state problem. In a first approximation involving only multiple ladder-type diagrams, and neglecting retardation effects altogether, an equivalent Hamiltonian is derived which contains as potential energy merely the static Yukawa potentials of the three nucleon pairs. If the retardation corrections are treated as small perturbations, e.g., in a scalar theory, the resulting three-particle interactions prove to be small of the second order, and no larger than those deriving from other classes of Feynman diagrams.