2s–3s excitation for positron–metastable hydrogen collisions

Positron impact differential cross sections for the excitation of atomic hydrogen from its metastable 2s state to 3s state at three incident energies, 10, 40 and 50 eV, are calculated using the momentum-space coupled-channel optical method. The influence of ionization continuum and positronium formation channels in this excitation process is investigated. Integrated cross sections are also reported over an energy region 10–200 eV. The present results are compared with available theoretical results.