Collisional Quenching of Metastable Hydrogen Atoms

Abstract

Quenching of metastable hydrogen atoms by low energy collisions with atoms and molecules is considered, the actual process being $\mathrm{H}\text{(2s)+}\mathrm{X}\to \mathrm{H}\text{(2p)+}\mathrm{X}$ . The Born approximation, with long‐range multipole–multipole interactions, is used to describe collisions of $\mathrm{H}\text{(2s)}$ with molecules, and simple formulas for the cross section result. Collisions with spherically symmetric species (i.e., rare gas atoms) are treated in the adiabatic approximation, and the process is seen to be formally identical to symmetric charge transfer. Numerical results for collisional quenching by helium, based on accurately computed potential curves, are presented.