Differential cross sections for electron-impact excitation of hydrogenlike ions

Abstract
A systematic study is made of differential cross sections for the electron-impact excitation of the 2s and 2p states of H-like ions. The cross section is calculated in the Coulomb-Born and the Coulomb-Born-Oppenheimer approximations. A comparison of the resulting cross sections is made along the isoelectronic sequence from Z=1 to (Z being the nuclear charge) to reveal the role of the Coulomb force in the excitation processes. For the 1s-2p transition, the behavior of the apparent generalized oscillator strength for the ions is found to be different from that for neutral hydrogen.