Proton collisions with hydrogen atoms at low energies: quantum theory and integrated cross-sections

Abstract

Cross-sections for collisions of protons with hydrogen atoms have been computed by partial wave analysis within the perturbed stationary state theory. Phase shifts with 6 decimal accuracy were obtained by the use of adiabatically corrected 1Sσ g and 2Pσ u H + 2 potentials together with accurate numerical methods. The phase shifts and the integrated cross-sections derived from them are reported for 57 values of the energy ranging from 0.0001 eV (1.2 K) to 10 eV. These accurate quantum mechanical results differ from semi-classical results especially at energies below 0.1 eV.