Modelizacao consistente e estudo experimental de uma descarga produzida por uma onda de superficie em argon numa instalacao experimental coaxial

We present a self-contained theoretical description and an experimental investigation of azimuthally symmetric surface wave (SW) sustained discharges in argon at low pressure in a coaxial experimental setup with a central cylinder. The model is based on a complete set of equations, including Maxwell's equations for the SW field and the continuity and the momentum transfer equations for the electrons and the ions, which are solved subject to appropriate physical boundary conditions. The radially inhomogeneous plasma is described as a glossy dielectric medium with a complex permittivity #epsilon#_#rho#. The dependence of the electron-neutral collision frequency for momentum transfer, #nu#_c, on the electron energy is taken into account in #epsilon#_#rho# through the effective electron density, n_e_f_f, and the effective collision frequency, #nu#_e_f_f. Two types of calculations are worked out and compared to each other using electron collisional and transport data vs. The SW electric field calculated either assuming a Maxwellian electron energy distribution or from the solutions to the homogeneous Boltzmann equation. The above formulation provides a complete and self-contained description of the spatial distributions of the SW sustaining field and the plasma density, of the wave dispersion relation, and of all the details about the power transfer the wave to the plasma. The theoretical results are compared to experimental data from electric and magnetic field measurements, and Langmuir probe and spectroscopic diagnostic. Finally, a general discussion of all the results is givenAvailable from Fundacao para a Ciencia e a Tecnologia, Servico de Informacao e Documentacao, Av. D. Carlos I, 126, 1200 Lisboa / FCT - Fundação para o Ciência e a TecnologiaSIGLEPTPortuga