A fluid model of the bulk plasma in a cylindrical magnetized low-pressure RF discharge and comparison with PIC - MC simulation results

The modelling of a cylindrical low-pressure RF discharge in a strong axial magnetic field is analysed by a comparison of previously obtained kinetic particle-in-cell - Monte Carlo (PIC - MC) simulation results to a newly developed hydrodynamic model. We show that such a model is possible in the bulk of the discharge, where the electron distribution function is Maxwellian to good accuracy. The small electron diffusion coefficient perpendicular to the magnetic field is essential for the validity of the hydrodynamic analysis. As a result, we obtain good agreement between the hydrodynamic model and our kinetic simulation data. We furthermore exemplify the usefulness of the hydrodynamic approach by discussing the properties of the discharge bulk in terms of macroscopic quantities; we thus can show that the contribution of thermal diffusion to the electron current is of the same importance as that of ordinary diffusion, an issue usually overlooked in the analysis of magnetized discharges.