Deactivation of He 2³S by thermal electrons

The rate coefficient for deactivation of the metastable 23S state of He by impact of thermal electrons is deduced from recent calculations of inelastic electron-He cross sections. The deactivation rate is found to be nearly constant with temperature. Computed values range between 2.82 and 3.03 (10-9 cm3/sec) for T between 0 and 2000°K. De-excitation cross sections are given for low-energy incident electrons. © 1974.