3s and 3p excitations of atomic hydrogen by proton and α-particle impact

Abstract
The authors have investigated the excitation of hydrogen atoms by alpha particle impact and by proton impact from the ground state to the 3s and 3p levels in the energy range 30 to 2000keV using the method of distortion. A comparison of their results with the corresponding results obtained by the first and second born and the approximation of Cheshire and Sullivan (1967) shows that the effect of distortion is to reduce the cross sections and that this effect is greater on 1s to 3s transition than on 1s to 3p transition.