An asymptotic solution for currents in the penumbra region with discontinuity in curvature

An analytical asymptotic result is obtained for evaluating the current distribution on a perfectly conducting surface composed of a flat plate smoothly joined to a parabolic cylinder with the join in the penumbra region. The result presents some improvements over a previous solution of the current distribution obtained by other investigators. The analytical result can be conveniently applied to estimating the backscattering cross section of a cone-sphere.