Separable expansions to local potentials in a quasipotential approach

A recently proposed method which was successfully used to make separable expansions for the nonrelativistic two-body t matrix is here used to construct separable expansions for the two-body t matrix satisfying relativistic unitarity in a quasipotential approach. The present method, unlike other commonly used methods, does not require the calculations of eigenfunctions and eigenvalues of the kernel of the scattering equations and yields simple form factors. The method is illustrated for a simple nucleon-nucleon potential in the context of the Blankenbecler-Sugar equation