Momentum-space coupled-channel calculation for positron-helium scattering

Abstract

The momentum-space coupled-channel optical method has been applied to positron-helium scattering. The ionization continuum and the positronium formation channels are included via a complex equivalent-local optical potential. The positronium formation cross sections at the energy range from the threshold to $400\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$ and the total scattering cross sections at the energies from 17 to $500\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$ are reported and compared with available experimental measurements and theoretical calculations. The agreements between the present results and the corresponding measurements are satisfactory.