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

Journal Article · Thu Mar 15 04:00:00 EDT 2007 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.2712806· OSTI ID:20953389

Luo, Y; Heidbrink, W W; Burrell, K H; Kaplan, D H; Gohil, P ^[1]

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1. University of California, Irvine, California 92697 (United States)

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.

• OSTI ID: 20953389
• Journal Information: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 3 Vol. 78; ISSN 0034-6748; ISSN RSINAK
• Country of Publication: United States
• Language: English

Related Subjects

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