A self-consistent analysis of a collisional presheath

A one-dimensional plasma discharge is analyzed under steady state condition s. Using simple models for source and collisions, a first-order differentia l equation is obtained that simultaneously describes both the bulk and the presheath of the plasma. This equation is numerically solved in various reg imes and physically interesting quantities such as the ratio of bulk to edg e density and the size of the inertial terms in the bulk region are present ed. Analytic expressions are obtained for profiles when collision frequency is assumed constant. Findings include n(B)/n(SE)similar to 2.5 for highly collisional systems, significant flow in the bulk plasma, and modified I-V characteristics. (C) 1999 American Institute of Physics. [S1070-664X(99)043 12-8].