Cross sections for 11–14-eVe-H2resonant collisions: Vibrational excitation

Abstract

Resonant vibrational excitation (RVE) cross sections have been calculated for the electron-${\text{H}}_{2}$ molecule collisions in the energy range 11--14 eV involving the ${^{2}\ensuremath{\Sigma}}_{g}^{+}$ excited electronic state of the molecular hydrogen ion $\text{H}_{2}{}^{\ensuremath{-}}$. This state, whose threshold is located around 14 eV, gives rise to the so-called series $a$ of the observed peaks in electron-impact differential cross-section measurements. The calculations have been performed within the local complex potential approximation by using the available theoretical potential energy and width for the ${^{2}\ensuremath{\Sigma}}_{g}^{+}$ resonant state. The cross sections for all ${v}_{i}=0\ensuremath{\rightarrow}{v}_{f}=1--14$ RVE transitions have been calculated. A satisfactory agreement of calculated cross sections with the available experimental data is obtained.