3-PARTICLE COULOMB ON-SHELL VERTEX FUNCTIONS - BEHAVIOR OF THE AMPLITUDE FOR SIMULTANEOUS TRANSFER OF 2 CHARGED-PARTICLES IN THE VICINITY OF THE NEAREST SINGULARITY IN COS-THETA

The connection between the on-shell vertex function (OSVF) and the asy mptotic normalized coefficient of the three-particle wave function of the bound system in the configuration space is found. The explicit for m of the leading singular term of the OSVF and its Faddeev component f or decay of the three-particle bound state into three charged particle s is established. An expression is found for the leading singular term of the exact (in the model of four charged particles) amplitude of su b-Coulomb binary reactions in the vicinity of the nearest singularity.