Cylindrical probe in anisotropic plasma: how can we achieve reliable results?
- 1 — Ph.D., Dr.Sci. professor National Mineral Resources University (Mining University)
- 2 — post-graduate student National Mineral Resources University (Mining University)
Abstract
It has been demonstrated, that cylindrical probe in anisotropic plasma allows to measure only the even components of the electron velocity distribution expansion. For the first time the method for determining the odd moments of the distribution function by solving a system of ki-netic Boltzmann equations, connecting the even and odd moments ( f0, f 1); ( f0, f 1, f2) etc. has been developed. The method was tested in plasma of low-voltage beam discharge in helium. The experimental probe I- V traces for different orientations of a cylindrical probe with respect to the axis of symmetry of the plasma has been obtained. The moments of f0 and f2 has been cal-culated, f1 moment is defined by solving the «vector» kinetic equation. The accuracy of f1 calculation controlled by coincidence of calculated and measured values of discharge current. Theoretical and experimental values are in a good agreement.
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