Proton-impact excitation of helium to then=2 sublevels in the distorted-wave Born approximation

Abstract
Differential and total cross sections for proton-impact excitation of helium to the n=2 sublevels are calculated in the distorted-wave Born approximation. Many-parameter correlated wave functions are used to describe the helium atom. A comparison with recent theories and experimental measurements is made. The present calculations for differential cross sections for the n=2 substates yield good agreement with the measured values of Park et al. and Kvale et al. and the multistate eikonal calculations of Flannery and McCann.