Measurement of plasma parameters in the PBI using the Langmuir probe

Abstract

When studying the processes of plasma interaction with the surface, there is a need to determine the exposure parameters and the installation operating modes. The goal of this work is to measure the plasma parameters on a plasma beam installation (PBI) using an automated probe diagnostics system developed by us.The plasma diagnostic and monitoring system at PBI is based on the use of a cylindrical Langmuir probe. The software has been developed for measuring, recording and processing the probe voltage characteristic (I-U curve) in real time and a movable probe input for measuring the radial distribution of the plasma parameters (plasma concentration, electronic temperature). The measurements were carried out under different operating modes of the PBI with a variation in the parameters of the accelerating voltage of the electron beam and the pressure of the working gas. The nature of changes in the plasma parameters in the radial direction in a hydrogen medium has been established. The obtained results are in good agreement with the similar work in the study of the plasma parameters in the radial direction at the linear plasma installations.The got dependences make it possible to analyze and establish a correspondence between the parameters of plasma action on materials and the nature of processes on their surface and in volume. The presented engineering idea will be proposed to complement the diagnostic complex of the plasma KTM tokamak.