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Title: Spontaneous multi-keV electron generation in a low-RF-power axisymmetric mirror machine

Abstract

X-ray emission reflects the existence of multikilo-electron-volt 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 imply that collisionless scattering—μ nonconservation 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 is 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-accelerationlike mechanism is shown, with μ nonconservation in the static vacuum field as an essential feature.

Authors:
ORCiD logo [1]; ORCiD logo [2]
  1. Princeton Satellite Systems, Plainsboro, NJ (United States)
  2. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Publication Date:
Research Org.:
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1543453
Alternate Identifier(s):
OSTI ID: 1525335
Grant/Contract Number:  
AC02-09CH11466
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 26; Journal Issue: 6; Journal ID: ISSN 1070-664X
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats

Swanson, Charles, and Cohen, S. A. Spontaneous multi-keV electron generation in a low-RF-power axisymmetric mirror machine. United States: N. p., 2019. Web. doi:10.1063/1.5093905.
Swanson, Charles, & Cohen, S. A. Spontaneous multi-keV electron generation in a low-RF-power axisymmetric mirror machine. United States. https://doi.org/10.1063/1.5093905
Swanson, Charles, and Cohen, S. A. 2019. "Spontaneous multi-keV electron generation in a low-RF-power axisymmetric mirror machine". United States. https://doi.org/10.1063/1.5093905. https://www.osti.gov/servlets/purl/1543453.
@article{osti_1543453,
title = {Spontaneous multi-keV electron generation in a low-RF-power axisymmetric mirror machine},
author = {Swanson, Charles and Cohen, S. A.},
abstractNote = {X-ray emission reflects the existence of multikilo-electron-volt 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 imply that collisionless scattering—μ nonconservation 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 is 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-accelerationlike mechanism is shown, with μ nonconservation in the static vacuum field as an essential feature.},
doi = {10.1063/1.5093905},
url = {https://www.osti.gov/biblio/1543453}, journal = {Physics of Plasmas},
issn = {1070-664X},
number = 6,
volume = 26,
place = {United States},
year = {2019},
month = {6}
}

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