Convergent close coupling calculations for positron-magnesium scattering

While a two-centre convergent close-coupling approach to positron-magnesium scattering is developed, a single-centre method has been used to calculate total cross sections up to incident energies of 100 eV. The results agree very well with the measurements of Stein et al. [1] for positron energies above the ionisation threshold (7.6 eV). Similar accuracy is expected for energies below the positronium formation threshold (0.8 eV) where presently there are no experimental data to compare to. In this energy region we find a large p-wave resonance at 0.17 eV. Similar resonance behaviour was found in calculations by Mitroy and Bromley [2] at an energy of 0.1 eV.