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arXiv · 1607.02851

Microscopic theory of electron absorption by plasma-facing surfaces

Franz X. Bronold·Holger Fehske
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Abstract

We describe a method for calculating the probability with which the wall of a plasma absorbs an electron at low energy. The method, based on an invariant embedding principle, expresses the electron absorption probability as the probability for transmission through the wall's long-range surface potential times the probability to stay inside the wall despite of internal backscattering. To illustrate the approach we apply it to a \SiOTwo\ surface. Besides emission of optical phonons inside the wall we take elastic scattering at imperfections of the plasma-wall interface into account and obtain absorption probabilities significantly less than unity in accordance with available electron-beam scattering data but in disagreement with the widely used perfect absorber model.

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Franz X. Bronold, Holger Fehske. 2016-07-11. Microscopic theory of electron absorption by plasma-facing surfaces. https://doi.org/10.1088/0741-3335%2F59%2F1%2F014011

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