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Title: Cyclotron resonance phenomena in a non-neutral multispecies ion plasma

Abstract

Cyclotron modes of a non-neutral Mg ion plasma were studied in a long cylindrical Penning--Malmberg trap. Several modes with angular dependence exp({ital il}{theta}), {ital l}{ge}1, are observed near the cyclotron frequencies of the various Mg ions. The {ital l}=1 modes for the majority species are downshifted from the cyclotron frequencies, with downshifts as large as four times the diocotron frequency. These large shifts are quantitatively explained by a multispecies cold-plasma theory, including the dependence on the plasma size and composition. These dependencies allow the plasma size and composition to be obtained from the measured mode frequencies. In contrast, the {ital l}=1 downshifts for minority species are generally close to twice the diocotron frequency, and remain unexplained. Cyclotron heating of the plasma ions was also observed with a surprising effect of improving the plasma confinement. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

Authors:
; ;  [1]
  1. Institute for Pure and Applied Physical Sciences and Department of Physics, University of California at San Diego, La Jolla, California 92093 (United States)
Publication Date:
OSTI Identifier:
165363
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 2; Journal Issue: 8; Other Information: PBD: Aug 1995
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION; MAGNESIUM IONS; ION CYCLOTRON-RESONANCE; CYCLOTRON FREQUENCY; COLD PLASMA; ICR HEATING; MASS SPECTROSCOPY; MULTICHARGED IONS

Citation Formats

Sarid, E., Anderegg, F., and Driscoll, C.F.. Cyclotron resonance phenomena in a non-neutral multispecies ion plasma. United States: N. p., 1995. Web. doi:10.1063/1.871189.
Sarid, E., Anderegg, F., & Driscoll, C.F.. Cyclotron resonance phenomena in a non-neutral multispecies ion plasma. United States. doi:10.1063/1.871189.
Sarid, E., Anderegg, F., and Driscoll, C.F.. 1995. "Cyclotron resonance phenomena in a non-neutral multispecies ion plasma". United States. doi:10.1063/1.871189.
@article{osti_165363,
title = {Cyclotron resonance phenomena in a non-neutral multispecies ion plasma},
author = {Sarid, E. and Anderegg, F. and Driscoll, C.F.},
abstractNote = {Cyclotron modes of a non-neutral Mg ion plasma were studied in a long cylindrical Penning--Malmberg trap. Several modes with angular dependence exp({ital il}{theta}), {ital l}{ge}1, are observed near the cyclotron frequencies of the various Mg ions. The {ital l}=1 modes for the majority species are downshifted from the cyclotron frequencies, with downshifts as large as four times the diocotron frequency. These large shifts are quantitatively explained by a multispecies cold-plasma theory, including the dependence on the plasma size and composition. These dependencies allow the plasma size and composition to be obtained from the measured mode frequencies. In contrast, the {ital l}=1 downshifts for minority species are generally close to twice the diocotron frequency, and remain unexplained. Cyclotron heating of the plasma ions was also observed with a surprising effect of improving the plasma confinement. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.},
doi = {10.1063/1.871189},
journal = {Physics of Plasmas},
number = 8,
volume = 2,
place = {United States},
year = 1995,
month = 8
}
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