Assessment of the spatial distribution of low-temperature plasma parameters on plasma-beam installation

Abstract

At present continue, studies of the interaction of plasma with structural materials of the first wall and divertor of the ITER international experimental fusion reactor on operating tokamaks and simulated plasma facilities. In the research of the interaction of plasma with the surface of candidate materials TNR an important role plasma parameters play. For determination of local values of the main plasma parameters there is a separate field of research – plasma diagnostics. Plasma diagnostics is the determination of local and instantaneous values of main its parameters: concentration and temperature of charged plasma particles, as well as the distribution functions of various plasma components by energies.This works presents the results of a research to the spatial distribution of local parameters (temperature electrons (Te) and plasma concentration (ne)) of a low-temperature plasma on a plasma-beam installation (PBI) with the help a movable Langmuir probe with the following geometrical parameters of the electrode: length – 4 mm; diameter 0.5 mm. The probe sweep was with the help a Keithley 6487 picoammeter. The processing of volt-ampere characteristics (VAC) was carried out by standard methods.To assess the spatial distribution of the above-mentioned parameters of low-temperature plasma, experiments were carried out with the location of the probe at a distance of 5 mm, 9 mm and 11 mm from the center of the plasma beam at different energies of the primary electron beam in the range from 0.5 keV to 5 keV.The experiments results showed a smooth decrease in plasma concentration in the radial direction.