Transport and turbulence experiments in three regimes of a magnetized plasma

The occurrence of turbulence and its influence on plasma viscosity have been investigated. A simple model of turbulence has been obtained by the balance of the growth of the combined Rayleigh-Taylor and Kelvin-Helmholtz instability, with the damping by friction against the neutrals, by kinetic viscosity and by turbulent viscosity itself. In the experiment with a hollow cathode arc, three regimes can be distinguished: a kinetic, a frictional and a turbulent regime. By variations of the discharge parameters around a suitably chosen operating point, transitions between the three regimes are caused. It appears that the longitudinal drift velocity is also influenced by the turbulence. A dispersion relation for the large scale oscillation of the whole arc has been derived and checked experimentall