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Title: Detection of electron energy distribution function anisotropy in a magnetized electron cyclotron resonance plasma by using a directional Langmuir probe

Abstract

Anisotropy in the electron energy distribution function (EEDF) in an electron cyclotron resonance plasma with magnetized electrons and weakly magnetized ions is experimentally investigated using a directional Langmuir probe. Under an assumption of independent EEDFs in the directions parallel and perpendicular to the magnetic field, the directional variation of the EEDF is evaluated. In the measured EEDFs, a significantly large population density of electrons with energies larger than 30 eV is found in one of the cross-field directions depending on the magnetic field direction. With the aid of an electron trajectory calculation, it is suggested that the observed anisotropic electrons originate from the EEDF anisotropy and the cross-field electron drift.

Authors:
;  [1];  [2]
  1. Department of Mechanical Engineering and Science, Graduate School of Engineering, Kyoto University, Kyoto 615-8540 (Japan)
  2. Faculty of Engineering, Undergraduate School of Engineering Science, Kyoto University, Kyoto 615-8540 (Japan)
Publication Date:
OSTI Identifier:
22299857
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 21; Journal Issue: 7; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; ANISOTROPY; DETECTION; ELECTRON CYCLOTRON-RESONANCE; ELECTRON DRIFT; ENERGY SPECTRA; EV RANGE 10-100; IONS; LANGMUIR PROBE; MAGNETIC FIELDS; PLASMA; TRAJECTORIES

Citation Formats

Shikama, T., E-mail: shikama@me.kyoto-u.ac.jp, Hasuo, M., and Kitaoka, H. Detection of electron energy distribution function anisotropy in a magnetized electron cyclotron resonance plasma by using a directional Langmuir probe. United States: N. p., 2014. Web. doi:10.1063/1.4890350.
Shikama, T., E-mail: shikama@me.kyoto-u.ac.jp, Hasuo, M., & Kitaoka, H. Detection of electron energy distribution function anisotropy in a magnetized electron cyclotron resonance plasma by using a directional Langmuir probe. United States. doi:10.1063/1.4890350.
Shikama, T., E-mail: shikama@me.kyoto-u.ac.jp, Hasuo, M., and Kitaoka, H. 2014. "Detection of electron energy distribution function anisotropy in a magnetized electron cyclotron resonance plasma by using a directional Langmuir probe". United States. doi:10.1063/1.4890350.
@article{osti_22299857,
title = {Detection of electron energy distribution function anisotropy in a magnetized electron cyclotron resonance plasma by using a directional Langmuir probe},
author = {Shikama, T., E-mail: shikama@me.kyoto-u.ac.jp and Hasuo, M. and Kitaoka, H.},
abstractNote = {Anisotropy in the electron energy distribution function (EEDF) in an electron cyclotron resonance plasma with magnetized electrons and weakly magnetized ions is experimentally investigated using a directional Langmuir probe. Under an assumption of independent EEDFs in the directions parallel and perpendicular to the magnetic field, the directional variation of the EEDF is evaluated. In the measured EEDFs, a significantly large population density of electrons with energies larger than 30 eV is found in one of the cross-field directions depending on the magnetic field direction. With the aid of an electron trajectory calculation, it is suggested that the observed anisotropic electrons originate from the EEDF anisotropy and the cross-field electron drift.},
doi = {10.1063/1.4890350},
journal = {Physics of Plasmas},
number = 7,
volume = 21,
place = {United States},
year = 2014,
month = 7
}
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