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 ji, floating potential Uf, energy flux density q, ion energy reflection coefficient RE and sheath energy transmission coefficient γ) were determined as functions of the angle α between the probe surface normal and the magnetic field. A geometric model has been developed to explain the ion flux density at grazing incidence.