## Analytic expressions for high-energy full three-dimensional continuum wave functions and phase shifts in screened-Coulomb potentials

Analytic expressions are obtained for nonrelativistic high-energy three-dimensional continuum wave functions (at small distances) and phase shifts in smoothed screened-Coulomb potentials of the form V(r) = -ag(lambdar)/r, where a = Z..cap alpha.., with ..cap alpha.. the fine structure constant, and lambda is a small parameter characterizing atomic screening (lambdaapprox. =..cap alpha..Z/sup 1/3/). For this purpose we combine information from an interation of an eikonal equation with an analytic perturbation theory (APT) for screened-Coulomb potentials, based on an expansion of the function g in the interior of the atom. Using the general three-dimensional APT solutions found previously, the particular solution whichmore »