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arXiv · 1901.10901

Spontaneous multi-keV electron generation from Fermi acceleration and magnetic moment non-adiabaticity

C. Swanson·S. A. Cohen
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Abstract

X-ray emission shows the existence of multi-keV electrons in low-temperature, low-power, capacitively-coupled RF-heated magnetic-mirror plasmas that also contain a warm (300 eV) minority electron population. Though these warm electrons are initially passing particles, we suggest that collisionless scattering - mu non-conservation in the static vacuum field - is responsible for a minority of them to persist in the mirror cell for thousands of transits during which time a fraction are energized to a characteristic temperature of 3 keV, with some electrons reaching energies above 30 keV. A heuristic model of the heating by a Fermi-acceleration-like mechanism is presented, with mu non-conservation in the static vacuum field as an essential feature.

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C. Swanson, S. A. Cohen. 2019-01-31. Spontaneous multi-keV electron generation from Fermi acceleration and magnetic moment non-adiabaticity. https://arxiv.org/abs/1901.10901

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