skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Plasma measurements from neutral-beam attenuation

Abstract

Extensive and informative plasma measurements have been made with the intense and energetic neutral-particle beams that are used for fueling and heating magnetically confined, controlled-fusion experimental plasmas. This diagnostic technique does not perturb the plasma because only the unused transmitted fraction of a neutral beam is detected. Orthogonal arrays of highly collimated detectors of the simple secondary-electron-emission type are used in magnetic-mirror experiments to measure neutral-beam attenuation (directly related to the plasma line density) along chords through the plasma volume at different radial and axial positions. Data from these arrays yield radial and axial plasma-density profiles, ion angular distributions at the plasma midplane, estimates of the neutral-beam input power to the plasma, and information on macroscopic plasma motion. Representative results obtained by applying this useful diagnostic technique to the recently completed tandem-mirror experiment TMX are included here. This diagnostic method can also be advantageously applied to other controlled-fusion experiments that use neutral-beam injection.

Authors:
; ;
Publication Date:
Research Org.:
Lawrence Livermore National Laboratory, University of California, Livermore, California 94550
OSTI Identifier:
6040360
DOE Contract Number:  
W-7405-ENG-48
Resource Type:
Journal Article
Journal Name:
Rev. Sci. Instrum.; (United States)
Additional Journal Information:
Journal Volume: 54:8
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; PLASMA DIAGNOSTICS; NEUTRAL ATOM BEAM INJECTION; ANGULAR DISTRIBUTION; ATTENUATION; COLLIMATORS; CONFINEMENT; ELECTRONS; HEATING; IONS; MAGNETIC FIELDS; MAGNETIC MIRRORS; NEUTRAL BEAM SOURCES; ORIENTATION; RADIATION DETECTORS; SECONDARY EMISSION; SPATIAL DISTRIBUTION; THERMONUCLEAR REACTORS; BEAM INJECTION; CHARGED PARTICLES; DISTRIBUTION; ELEMENTARY PARTICLES; EMISSION; FERMIONS; LEPTONS; MEASURING INSTRUMENTS; OPEN PLASMA DEVICES; THERMONUCLEAR DEVICES; 700102* - Fusion Energy- Plasma Research- Diagnostics

Citation Formats

Foote, J H, Molvik, A W, and Turner, W C. Plasma measurements from neutral-beam attenuation. United States: N. p., 1983. Web. doi:10.1063/1.1137504.
Foote, J H, Molvik, A W, & Turner, W C. Plasma measurements from neutral-beam attenuation. United States. https://doi.org/10.1063/1.1137504
Foote, J H, Molvik, A W, and Turner, W C. 1983. "Plasma measurements from neutral-beam attenuation". United States. https://doi.org/10.1063/1.1137504.
@article{osti_6040360,
title = {Plasma measurements from neutral-beam attenuation},
author = {Foote, J H and Molvik, A W and Turner, W C},
abstractNote = {Extensive and informative plasma measurements have been made with the intense and energetic neutral-particle beams that are used for fueling and heating magnetically confined, controlled-fusion experimental plasmas. This diagnostic technique does not perturb the plasma because only the unused transmitted fraction of a neutral beam is detected. Orthogonal arrays of highly collimated detectors of the simple secondary-electron-emission type are used in magnetic-mirror experiments to measure neutral-beam attenuation (directly related to the plasma line density) along chords through the plasma volume at different radial and axial positions. Data from these arrays yield radial and axial plasma-density profiles, ion angular distributions at the plasma midplane, estimates of the neutral-beam input power to the plasma, and information on macroscopic plasma motion. Representative results obtained by applying this useful diagnostic technique to the recently completed tandem-mirror experiment TMX are included here. This diagnostic method can also be advantageously applied to other controlled-fusion experiments that use neutral-beam injection.},
doi = {10.1063/1.1137504},
url = {https://www.osti.gov/biblio/6040360}, journal = {Rev. Sci. Instrum.; (United States)},
number = ,
volume = 54:8,
place = {United States},
year = {1983},
month = {8}
}