Two-center convergent-close-coupling calculations of positron scattering on magnesium

The two-center convergent-close-coupling method is extended to the calculation of positron scattering from atoms with two valence electrons above an inert ion core. Calculations of positron scattering on magnesium have been performed over a wide energy range. Elastic scattering, Positronium formation, target excitation, and direct ionization cross sections have been calculated. Results are in reasonably good agreement with the experimental data where available. Current results confirm the existence of a low-energy shape resonance predicted by variational and single-center convergent-close-coupling methods