The plasma–sheath transition in low temperature plasmas: on the existence of a collisionally modified Bohm criterion

Abstract

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Moment fluid equations for ions in weakly ionized plasma

“…In the case of argon, we also show the approximation presented in Ref. [19] and the results obtained using the data of Phelps [22] which are based on the theoretical model of Ref. [37].…”

“…Despite the fact that these equations are not always based on an explicitly stated kinetic model they have been shown to give reasonable results under certain conditions. Moreover, such models are widely used to analyze the presheath-sheath transition in weakly-ionized plasma [16][17][18][19]. Nevertheless, two points can be made regarding the applicability and accuracy of the fluid equations for ions.…”

Interaction of biased electrodes and plasmas: sheaths, double layers, and fireballs

“…This is likely because the two ion species are collisionally decoupled from one another at this pressure, so the assumptions of the model apply to each species individually. Describing how collisions modify the Bohm criterion remains a topic of continuing research [151,152].…”

Collisionless “thermalization” in the sheath of an argon discharge

“…c s at the entrance of the sheath, with no appreciable collision-induced corrections. 25,26 B. Evolution of the IVDF from bulk to wall…”