Demonstration of fast-electron populations in a low-pressure, low-power, magnetized RF plasma source

Jandovitz, P.; Swanson, C.; Matteucci, J.; Oliver, R.; Pearcy, J.; Cohen, S. A.

doi:10.1063/1.4998735

Title: Demonstration of fast-electron populations in a low-pressure, low-power, magnetized RF plasma source

Journal Article · Tue Mar 27 00:00:00 EDT 2018 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.4998735· OSTI ID:1460986

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Princeton Univ., Princeton, NJ (United States). Princeton Plasma Physics Lab.
Brown Univ., Providence, RI (United States)
Princeton Univ., Princeton, NJ (United States)

Using x-ray spectroscopy, we demonstrate the existence of 0.3–6 keV electrons in a low-pressure, low-power, magnetized plasma source, heated by an external radio-frequency antenna located at one end of an axisymmetric tandem mirror. X-ray measurements on low-bulk-temperature, T_e,b ~ 4 eV, hydrogen, neon, argon, and gas-mixture plasmas show spectra with high-energy tails having a near-Maxwellian form with T_e,f up to 650 eV. Furthermore, the fast electrons producing these x-rays have densities in the range of 10⁷–10⁹ cm^–3 0.01%–1% of the bulk plasma density (up to 3 × 10¹¹ cm^–3), and so carry a significant fraction of the plasma energy and represent an important mechanism relevant to power coupling and heat flow in similar plasma sources.

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Research Organization:: Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)

Sponsoring Organization:: USDOE

Grant/Contract Number:: AC02-09CH11466

OSTI ID:: 1460986

Alternate ID(s):: OSTI ID: 1429954

Journal Information:: Physics of Plasmas, Vol. 25, Issue 3; ISSN 1070-664X

Publisher:: American Institute of Physics (AIP)Copyright Statement

Country of Publication:: United States

Language:: English

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Cited by: 5 works

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Cited By (1)

Spontaneous multi-keV electron generation in a low-RF-power axisymmetric mirror machine Swanson, C.; Cohen, S. A. Physics of Plasmas, Vol. 26, Issue 6 https://doi.org/10.1063/1.5093905	journal	June 2019