POSITRON SCATTERING FROM ARGON

The authors have extended their work on the polarised-orbital approximation to the calculation of scattering and annihilation processes for the positron-argon system in the elastic-scattering region. They present results 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 authors have also investigated the angular distribution of the scattered positron and the possibility of forming a bound state of the system. The model predicts that there is no bound state of the positron-argon system.