Propagation characteristics of surface waves sustaining atmospheric pressure discharges: the influence of the discharge processes

The propagation characteristics of microwave frequency surface waves along atmospheric pressure plasma columns sustained in capillary tubes by these same waves are studied analytically and numerically. In contrast to what has been done to date in such a pressure range, our analysis includes the modelling of the discharge processes in order to account for their interdependence with the wave's propagation. To describe these processes and to determine the plasma parameters, we turn to a two-temperature model for non-equilibrium plasmas. The analysis of the wave dispersion is performed using a cold plasma, linear dielectric description; it assumes the local uniformity approximation, which is scrutinized. Also, we assume that the phase and attenuation coefficients of the wave, under given discharge conditions, depend only on the amount of power dissipated in the plasma per unit length. The obtained results are compared with known experimental data.