Electron collisions with molecular hydrogen from electronically excited states using the R-matrix method

Abstract

Cross section data for electron impact electronic excitation of electronically excited states of H2 are computed using fixed-nuclear R-matrix calculations. Specifically, there is a focus on transitions from the quasi-metastable excited states a3Sg+ and c 3?u. Data are compared with known theoretical data where available. Our calculations suggest that the published cross sections are generally too large in the low energy (<20 eV) collision region. The effect of shifting the electronic excitation thresholds to those given by essentially exact calculations is tested.