A novel numerical tool to study electron energy distribution functions\n of spatially-anisotropic and non-homogeneous ECR plasmas

Abstract

A numerical tool for analysing spatially anisotropic electron populations in\nelectron cyclotron resonance (ECR) plasmas has been developed, using a\ntrial-and-error electron energy distribution function (EEDF) fitting method.\nThe method has been tested on space-resolved warm electrons in the energy range\n$2-20\\,\\mathrm{keV}$, obtained from self-consistent simulations modelling only\nelectron dynamics in ECR devices, but lacked real-world validation. For\nexperimentally benchmarking the method, we attempted to numerically reproduce\nthe experimental X-ray emission spectrum measured from an argon plasma. Results\nof this analysis have provided crucial information about density and\ntemperature of warm electrons, and competing distributions of warm and hot\nelectron components. This information can be fed back to simulation models to\ngenerate more realistic data. Subsequent application of the numerical tool as\ndescribed to the improved simulation data can result in continuous EEDFs that\nreflect the nature of charge distributions in anisotropic ECR plasmas. These\nfunctions can be also applied to electron dependent reactions, in order to\nreproduce experimental results, like those concerning space-dependent K$\\alpha$\nemissions.\n