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Title: Trivelpiece-Gould modes in a uniform unbounded plasma

Abstract

Trivelpiece-Gould (TG) modes originally described electrostatic surface waves on an axially magnetized cylindrical plasma column. Subsequent studies of electromagnetic waves in such plasma columns revealed two modes, a predominantly magnetic helicon mode (H) and the mixed magnetic and electrostatic Trivelpiece-Gould modes (TG). The latter are similar to whistler modes near the oblique cyclotron resonance in unbounded plasmas. The wave propagation in cylindrical geometry is assumed to be paraxial while the modes exhibit radial standing waves. The present work shows that TG modes also arise in a uniform plasma without radial standing waves. It is shown experimentally that oblique cyclotron resonance arises in large mode number helicons. Their azimuthal wave number far exceeds the axial wave number which creates whistlers near the oblique cyclotron resonance. Cyclotron damping absorbs the TG mode and can energize electrons in the center of a plasma column rather than the edge of conventional TG modes. The angular orbital field momentum can produce new perpendicular wave-particle interactions.

Authors:
;  [1]
  1. Department of Physics and Astronomy, University of California, Los Angeles, California 90095-1547 (United States)
Publication Date:
OSTI Identifier:
22599862
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 9; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CYCLOTRON RESONANCE; CYCLOTRONS; CYLINDRICAL CONFIGURATION; ELECTRONS; PARTICLE INTERACTIONS; PLASMA; STANDING WAVES; WAVE PROPAGATION; WHISTLER INSTABILITY; WHISTLERS

Citation Formats

Stenzel, R. L., and Urrutia, J. M. Trivelpiece-Gould modes in a uniform unbounded plasma. United States: N. p., 2016. Web. doi:10.1063/1.4962182.
Stenzel, R. L., & Urrutia, J. M. Trivelpiece-Gould modes in a uniform unbounded plasma. United States. doi:10.1063/1.4962182.
Stenzel, R. L., and Urrutia, J. M. 2016. "Trivelpiece-Gould modes in a uniform unbounded plasma". United States. doi:10.1063/1.4962182.
@article{osti_22599862,
title = {Trivelpiece-Gould modes in a uniform unbounded plasma},
author = {Stenzel, R. L. and Urrutia, J. M.},
abstractNote = {Trivelpiece-Gould (TG) modes originally described electrostatic surface waves on an axially magnetized cylindrical plasma column. Subsequent studies of electromagnetic waves in such plasma columns revealed two modes, a predominantly magnetic helicon mode (H) and the mixed magnetic and electrostatic Trivelpiece-Gould modes (TG). The latter are similar to whistler modes near the oblique cyclotron resonance in unbounded plasmas. The wave propagation in cylindrical geometry is assumed to be paraxial while the modes exhibit radial standing waves. The present work shows that TG modes also arise in a uniform plasma without radial standing waves. It is shown experimentally that oblique cyclotron resonance arises in large mode number helicons. Their azimuthal wave number far exceeds the axial wave number which creates whistlers near the oblique cyclotron resonance. Cyclotron damping absorbs the TG mode and can energize electrons in the center of a plasma column rather than the edge of conventional TG modes. The angular orbital field momentum can produce new perpendicular wave-particle interactions.},
doi = {10.1063/1.4962182},
journal = {Physics of Plasmas},
number = 9,
volume = 23,
place = {United States},
year = 2016,
month = 9
}
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