Angular dependence of energy and particle fluxes in a magnetized plasma

A flat probe allowing simultaneous measurements of energy flux and current density as functions of a bias voltage was rotated in a spatially homogeneous plasma. The experiments were conducted at the PSI-2 facility, a linear divertor simulator with moderate magnetic field strength. Sheath parameters (ion current density j(i), floating potential U-r, energy flux density q, ion energy reflection coefficient R-E and sheath energy transmission coefficient gamma) were determined as functions of the angle alpha between the probe surface normal and the magnetic field. A geometric model has been developed to explain the ion flux density at grazing incidence. (c) 2004 Elsevier B.V. All rights reserved.