Elastic scattering of positrons and electrons by argon

Differential and integrated cross sections for the elastic scattering of low- and intermediate-energy (3–300 eV) positrons and electrons by argon atoms are calculated. Higher transport cross sections, representing moments of 1-(costheta${)}^n$, for these systems are also obtained for n=1–4. Model potentials are used to represent the interactions between positrons or electrons and argon atoms. For each impact energy, the phase shifts of the lower partial waves are obtained exactly by numerical integration of the radial equation. The Born approximation is used to obtain the contribution of the higher partial waves to the scattering amplitude. The phase shifts of the seven lowest partial waves are tabulated for various impact energies of positrons and electrons.