Direct measurement of the transition from edge to core power coupling in a light-ion helicon source

被引：18

作者：

Piotrowicz, A. ^{[1
]}

Caneses, J. F. ^{[2
]}

Showers, M. A. ^{[2
]}

Green, D. L. ^{[3
]}

Goulding, R. H. ^{[3
]}

Caughman, J. B. O. ^{[3
]}

Biewer, T. M. ^{[3
]}

Rapp, J. ^{[3
]}

Ruzic, D. N. ^{[1
]}

机构：

[1] Univ Illinois, Champaign, IL 61801 USA

[2] Univ Tennessee, Knoxville, TN 37996 USA

[3] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA

来源：

PHYSICS OF PLASMAS | 2018年 / 25卷 / 05期

关键词：

PLASMA SOURCE; WAVES; MODES;

D O I：

10.1063/1.5023924

中图分类号：

O35 [流体力学]; O53 [等离子体物理学];

学科分类号：

070204 ; 080103 ; 080704 ;

摘要：

We present time-resolved measurements of an edge-to-core power transition in a light-ion (deuterium) helicon discharge in the form of infra-red camera imaging of a thin stainless steel target plate on the Proto-Material Exposure eXperiment device. The time-resolved images measure the two-dimensional distribution of power deposition in the helicon discharge. The discharge displays a mode transition characterized by a significant increase in the on-axis electron density and core power coupling, suppression of edge power coupling, and the formation of a fast-wave radial eigen-mode. Although the self-consistent mechanism that drives this transition is not yet understood, the edge-to-core power transition displays characteristics that are consistent with the discharge entering a slow-wave anti-resonant regime. RF magnetic field measurements made across the plasma column, together with the power deposition results, provide direct evidence to support the suppression of the slow-wave in favor of core plasma production by the fast-wave in a light-ion helicon source. Published by AIP Publishing.

引用

页数：5

共 31 条

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