Positronium formation during scattering of positrons by hydrogen atoms

Relevant data is available at: http://www.astronomy.ohio-state.edu/~nahar/nahar_radiativeatomicdata/index.htmlThe formation of positronium (Ps) in different states by the impact of intermediate energy (20-500 eV) positrons on atomic hydrogen is calculated using the distorted-wave Born approximation along with the first Born approximation. Differential and integrated cross sections for the formation of Ps(ls), Ps(2s), Ps(2p_0), and Ps(2p_1) have been evaluated individually and then 1/n^3 behavior for charge-transfer cross sections is used for n ≥ 3 to obtain the total cross sections for positronium formation. The present results for positronium formation cross sections are in agreement with the results of other available investigations