Positronium formation in positron-hydrogen scattering using Schwinger’s principle

Abstract

Accurate results are reported for ground-state positronium formation in positron-hydrogen collisions using 12 correlated basis functions in a multichannel Schwinger's principle in momentum space at intermediate energies 30--150 eV in an extension of our earlier work [Phys. Rev. A 59, 1913 (1999)]. The rich structure in the differential cross section is found to be present due to the existence of critical angles. Results for the total formation cross section are in excellent agreement with other variational and nonvariational calculations available in the literature. The observed data of Zhou et al. [Phys. Rev. A 55, 361 (1997)] are also in good accord with these predictions.