Quenching of atomic states in a low-pressure hydrogen glow discharge

Abstract

A laser perturbation method is used to determine the relaxation rates of levels $n=3, 4, 5$ of atomic hydrogen as a function of pressure and current intensity in a glow discharge. Quenching is due to spontaneous emission of radiation towards lower levels and to inelastic collisions with ${\mathrm{H}}_2$ molecules in the ground and quasimetastable states with thermally averaged cross sections of about 1.5×${10}^{-14\mathrm{}}$ ${\mathrm{cm}}^2$.