Kinetic theory of the plasma sheath transition in a weakly ionized plasma

The boundary layer of a weakly ionized rare gas discharge is treated using kinetic theory. A self-consistent two-scale analysis is performed and the exact presheath and sheath solutions are constructed for the following model: A plasma consisting of Boltzmann distributed electrons and singly charged atomic ions is in contact with a negative absorbing wall. The ion kinetics is dominated by charge exchange with cold neutrals (T0≪T−). The mean-free-path λ is constant and large compared with the electron Debye length λD. This model represents a collision-dominated counterpart to the well known Tonks–Langmuir model of the collision-free plasma.