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Title: Measurement of the D{sub {alpha}} spectrum produced by fast ions in DIII-D

Abstract

Fast ions are produced by neutral beam injection and ion cyclotron heating in toroidal magnetic fusion devices. As deuterium fast ions orbit around the device and pass through a neutral beam, some deuterons neutralize and emit D{sub {alpha}} light. For a favorable viewing geometry, the emission is Doppler shifted away from other bright interfering signals. In the 2005 campaign, we built a two channel charge-coupled device based diagnostic to measure the fast-ion velocity distribution and spatial profile under a wide variety of operating conditions. Fast-ion data are acquired with a time resolution of {approx}1 ms, spatial resolution of {approx}5 cm, and energy resolution of {approx}10 keV. Background subtraction and fitting techniques eliminate various contaminants in the spectrum. Neutral particle and neutron diagnostics corroborate the D{sub {alpha}} measurement. Examples of fast-ion slowing down and pitch angle scattering in quiescent plasma and fast-ion acceleration by high harmonic ion cyclotron heating are presented.

Authors:
; ; ; ;  [1];  [2]
  1. University of California, Irvine, California 92697 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
20953389
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 78; Journal Issue: 3; Other Information: DOI: 10.1063/1.2712806; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ACCELERATION; CHARGE-COUPLED DEVICES; CYCLOTRONS; DEUTERIUM; DEUTERONS; DOPPLER EFFECT; DOUBLET-3 DEVICE; ENERGY RESOLUTION; GEOMETRY; IONS; KEV RANGE; NEUTRAL PARTICLES; NEUTRONS; PLASMA BEAM INJECTION; PLASMA DIAGNOSTICS; QUIESCENT PLASMA; RF SYSTEMS; SPATIAL RESOLUTION; TIME RESOLUTION

Citation Formats

Luo, Y., Heidbrink, W. W., Burrell, K. H., Kaplan, D. H., Gohil, P., and General Atomics, San Diego, California 92186. Measurement of the D{sub {alpha}} spectrum produced by fast ions in DIII-D. United States: N. p., 2007. Web. doi:10.1063/1.2712806.
Luo, Y., Heidbrink, W. W., Burrell, K. H., Kaplan, D. H., Gohil, P., & General Atomics, San Diego, California 92186. Measurement of the D{sub {alpha}} spectrum produced by fast ions in DIII-D. United States. doi:10.1063/1.2712806.
Luo, Y., Heidbrink, W. W., Burrell, K. H., Kaplan, D. H., Gohil, P., and General Atomics, San Diego, California 92186. Thu . "Measurement of the D{sub {alpha}} spectrum produced by fast ions in DIII-D". United States. doi:10.1063/1.2712806.
@article{osti_20953389,
title = {Measurement of the D{sub {alpha}} spectrum produced by fast ions in DIII-D},
author = {Luo, Y. and Heidbrink, W. W. and Burrell, K. H. and Kaplan, D. H. and Gohil, P. and General Atomics, San Diego, California 92186},
abstractNote = {Fast ions are produced by neutral beam injection and ion cyclotron heating in toroidal magnetic fusion devices. As deuterium fast ions orbit around the device and pass through a neutral beam, some deuterons neutralize and emit D{sub {alpha}} light. For a favorable viewing geometry, the emission is Doppler shifted away from other bright interfering signals. In the 2005 campaign, we built a two channel charge-coupled device based diagnostic to measure the fast-ion velocity distribution and spatial profile under a wide variety of operating conditions. Fast-ion data are acquired with a time resolution of {approx}1 ms, spatial resolution of {approx}5 cm, and energy resolution of {approx}10 keV. Background subtraction and fitting techniques eliminate various contaminants in the spectrum. Neutral particle and neutron diagnostics corroborate the D{sub {alpha}} measurement. Examples of fast-ion slowing down and pitch angle scattering in quiescent plasma and fast-ion acceleration by high harmonic ion cyclotron heating are presented.},
doi = {10.1063/1.2712806},
journal = {Review of Scientific Instruments},
number = 3,
volume = 78,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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