Depopulation of Excited Mercury Atoms by Collisions with Hydrogen Molecules in the Flowing Mercury Afterglow

Using the steady state flowing afterglow method, hydrogen molecules in their ground states are introduced into the mercury afterglow plasma in which the dissociative recombination process is predominant, and the depopulation of the excited mercury states by collisions with hydrogen molecules are investigated. The quenching of the radiation emitted from 7³S₁ or 6³D state is explained by assuming that, after the dissociative recombination, the dissociated atom produced in the excited state of which transition probability is smaller than those of 7³S₁ and 6³D states is depopulated by collisions with hydrogen molecules. The resonance state 6³P₁ and the metastable state 6³P₀ are also quenched and these quenching cross sections are estimated to be _q1=6.6 Ų and _q0=0.25 Ų, respectively.