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Title: Measurements of neutral density profiles using a deuterium Balmer-alpha diagnostic in the C-2 FRC plasma

Abstract

In C-2 field-reversed configuration (FRC) device, low neutral density outside the FRC separatrix is required to minimize the charge exchange loss of fast particles. Titanium gettering is used in C-2 to reduce the wall recycling and keep the neutral density low in plasma edge. The measurements of neutral density radial profile are desirable to understand the plasma recycling and the effects of titanium gettering. These measurements are also needed to study the interaction of neutral beams with FRC plasma and confinement of fast ions. Diagnostic based on absolute deuterium Balmer-alpha (D-alpha) radiation measurements is developed and deployed on C-2 device to measure the radial profile of neutral density. Simultaneous measurements of electron density and temperature are done using CO{sub 2} interferometer, Thomson scattering, and triple probes diagnostics along with absolute D-alpha radiation. Abel inversion was performed to get the time dependent radial profile of the local D-alpha emission density. Neutral density profiles are obtained under different machine conditions of titanium deposition.

Authors:
; ; ; ;  [1]
  1. Tri Alpha Energy, Rancho Santa Margarita, California 92688 (United States)
Publication Date:
OSTI Identifier:
22093844
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 83; Journal Issue: 10; Other Information: (c) 2012 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; 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; BEAM-PLASMA SYSTEMS; BOUNDARY LAYERS; CARBON DIOXIDE; CHARGE EXCHANGE; DEUTERIUM; ELECTRON DENSITY; EMISSION; EQUIPMENT; FIELD-REVERSED THETA PINCH DEVICES; INTERACTIONS; INTERFEROMETERS; PLASMA; PLASMA CONFINEMENT; PLASMA DENSITY; PLASMA DIAGNOSTICS; REVERSED-FIELD PINCH DEVICES; REVERSE-FIELD PINCH; THOMSON SCATTERING; TIME DEPENDENCE; TITANIUM

Citation Formats

Gupta, Deepak K., Deng, B. H., Knapp, K., Sun, X., and Thompson, M. C.. Measurements of neutral density profiles using a deuterium Balmer-alpha diagnostic in the C-2 FRC plasma. United States: N. p., 2012. Web. doi:10.1063/1.4742141.
Gupta, Deepak K., Deng, B. H., Knapp, K., Sun, X., & Thompson, M. C.. Measurements of neutral density profiles using a deuterium Balmer-alpha diagnostic in the C-2 FRC plasma. United States. doi:10.1063/1.4742141.
Gupta, Deepak K., Deng, B. H., Knapp, K., Sun, X., and Thompson, M. C.. 2012. "Measurements of neutral density profiles using a deuterium Balmer-alpha diagnostic in the C-2 FRC plasma". United States. doi:10.1063/1.4742141.
@article{osti_22093844,
title = {Measurements of neutral density profiles using a deuterium Balmer-alpha diagnostic in the C-2 FRC plasma},
author = {Gupta, Deepak K. and Deng, B. H. and Knapp, K. and Sun, X. and Thompson, M. C.},
abstractNote = {In C-2 field-reversed configuration (FRC) device, low neutral density outside the FRC separatrix is required to minimize the charge exchange loss of fast particles. Titanium gettering is used in C-2 to reduce the wall recycling and keep the neutral density low in plasma edge. The measurements of neutral density radial profile are desirable to understand the plasma recycling and the effects of titanium gettering. These measurements are also needed to study the interaction of neutral beams with FRC plasma and confinement of fast ions. Diagnostic based on absolute deuterium Balmer-alpha (D-alpha) radiation measurements is developed and deployed on C-2 device to measure the radial profile of neutral density. Simultaneous measurements of electron density and temperature are done using CO{sub 2} interferometer, Thomson scattering, and triple probes diagnostics along with absolute D-alpha radiation. Abel inversion was performed to get the time dependent radial profile of the local D-alpha emission density. Neutral density profiles are obtained under different machine conditions of titanium deposition.},
doi = {10.1063/1.4742141},
journal = {Review of Scientific Instruments},
number = 10,
volume = 83,
place = {United States},
year = 2012,
month =
}
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