Large effects of small pressure changes in the kinetics of low pressure glow discharges
نویسندگان
چکیده
The effect of comparatively small pressure changes on the composition of low pressure hollow cathode DC discharges is investigated with a combination of experimental diagnostic techniques and simple models of the plasma kinetics. The plasma precursors considered are H2, Ar/H2 mixtures, and air. In all cases, sudden characteristic composition changes are observed in the pressure interval between ≈ 0.5 and 3 Pa. Focusing the analysis on these distinctive changes has revealed most useful for the identification of key physicochemical processes in the various plasmas investigated.
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