Continuum-distorted-wave-final-state approximation in positron-hydrogenic atom (ion) collisions with positronium formation.

Abstract

We study theoretically the formation of positronium atoms through electron capture in collisions of positrons impacting on hydrogenlike targets such as He{sup +}, Li{sup 2+}, and Be{sup 3+}. We obtain the scattering amplitude of the charge-exchange process by using a distorted-wave model derived from the first order of a Dodd and Greider{close_quote}s expansion. We compute differential and total cross sections by using a partial-wave technique. {copyright} {ital 1996 The American Physical Society.}