Cross sections for dissociative ionization and dissociative excitation of H2+ by single photon absorption

The photo-absorption cross sections for the dissociative ionization (DI) and dissociative excitation (DE) of H2+ are calculated for photon polarization parallel and perpendicular to the internuclear axis. The wavefunctions for the initial and final states are prepared using the Born-Oppenheimer approximation. For DI, the cross section and angular distribution of photo-electrons are compared with those calculated with the fixed-nuclei approximation. The obtained DI cross sections are in good agreement with earlier works. The dissociation energy of two protons peaks near E1 = 0.5, and the peak position does not depend as much on the photon energy. The results for the cross section and the photo-electron angular distribution are compared with those of the FN approximation. The effect of Young-type interference seen in the results of the FN approximation is weakened by taking into account internuclear motion. For perpendicular polarization, the results in the two calculations are relatively similar. For parallel polarization, the angular distributions in the two calculations may differ considerably at some energies. For dissociative excitation (DE), the cross sections for H (N = 1 - 4) productions are shown and the contributions from the related electronic states are discussed