Properties of ECR Plasma in a Simple Mirror Field II–Spatial Structure of the Plasma–

Abstract

The spatial structure of an ECR plasma in a simple mirror field was experimentally studied. From axial measurements of the cold plasma parameters it was found that a plasma can be efficiently confined between the two resonance zones in the axial direction, rather than between the mirror throats, when the gas pressure is low enough to produce sufficiently hot and/or warm electrons. While measuring the radial distribution of low-energy soft X-ray emissions, it was verified that the 2nd-harmonic, as well as the fundamental, resonance zones contribute remarkably to the production of hot and/or warm electrons.