Leptonic Decay Widths for the Composite System of Two Spin Particles with Equal Masses in the Relativistic Quasipotential Approach

Abstract

The new relativistic WKB expression for leptonic decay widths of the relativistic systems of two fermions with equal masses interacting by means of the funnel-type potentials is obtained. Quasipotential equation is solved by the WKB approximation. The behavior of the relativistic leptonic decay widths of vector mesons was investigated. Comparison of the behavior for new expression with its nonrelativistic spinless and relativistic spin and spinless analogues are given. Consideration is conducted within the framework of completely covariant quasipotential approach in the Hamiltonian formulation of quantum field theory, via a transition to the relativistic configurational representation in the case of two relativistic spin particles of equal masses.