TIME-DELAY IN SEMICLASSICAL SCATTERING-THEORY

An asymptotic evaluation of the time delay in the context of the semic lassical approximation is performed. It is shown that it is related to Stokes's discontinuities of the asymptotic series caused by singulari ties determined by the turning points and points of equilibrium of the effective potential in the complex tau-plane. The theory is applied t o the repulsive potentials inversely proportional to the fourth and th e sixth power of the distance. The case of complex potentials, usually considered in nuclear scattering is also discussed.