Positron scattering from argon

Previous work (McEachran et al. J. Phys. B.; 10: 663 (1977)) on the polarised-orbital approximation to the calculation of scattering and annihilation processes for the positron-argon system in the elastic-scattering region, is extended. Results are presented for the phaseshifts; the elastic, diffusion and annihilation cross sections; and the angular correlation of photons produced during annihilation. As in previous calculations the results are in very good agreement with various experimental measurements. The angular distribution of the scattered positron and the possibility of forming a bound state of the system have also been investigated. The model used predicts that there is no bound state of the positron-argon system. (author)