Strong Reduction of Ion Flux to a Target Plate in a Magnetically Contracting Detached Plasma

Abstract

Ion flux into a target plate in expanding and/or contracting magnetic field configuration has been measured under detached plasma condition in the linear plasma device NAGDIS-II. When the magnetic field was contracting towards the target plate, the strong reduction of the ion flux into the target was observed. This result indicates that the contraction in magnetic field should contribute to enhancing the degree of detachment. The magnetic-field-induced enhancement of electron density and the reduction of ion flow velocity due to the mirror effect in contracting magnetic field could lead to increasing volumetric recombination as well as the coupling between ions and electrons.