Measurements of Energy Distributions in ECR Plasma

This is the authors' abstract. We don't add key points for this paper.

The electron energy distribution is measured in an ECR device for H2 and N2 plasmas as a function of pressure. The maximum measurable energy and the high-energy tail increase with decreasing pressure. However, the energy distribution at the high-energy part progressively departs from a Maxwellian shape as the pressure is increased. The electron temperature obtained from the low-energy part increases with decreasing pressure. The positive ion temperature is of the order of a few eV and increases with the electron temperature. A mechanism of ion acceleration should exist.