Fast-ion transport by Alfven eigenmodes above a critical gradient threshold

被引：42

作者：

Heidbrink, W. W. ^{[1
]}

Collins, C. S. ^{[2
]}

Podesta, M. ^{[3
]}

Kramer, G. J. ^{[3
]}

Pace, D. C. ^{[2
]}

Petty, C. C. ^{[2
]}

Stagner, L. ^{[1
]}

Van Zeeland, M. A. ^{[2
]}

White, R. B. ^{[3
]}

Zhu, Y. B. ^{[1
]}

机构：

[1] Univ Calif Irvine, Irvine, CA 92697 USA

[2] Gen Atom, San Diego, CA 92186 USA

[3] Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA

来源：

PHYSICS OF PLASMAS | 2017年 / 24卷 / 05期

关键词：

ALPHA; CODE;

D O I：

10.1063/1.4977535

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：

Experiments on the DIII-D tokamak have identified how multiple simultaneous Alfven eigenmodes (AEs) lead to overlapping wave-particle resonances and stochastic fast-ion transport in fusion grade plasmas [C. S. Collins et al., Phys. Rev. Lett. 116, 095001 (2016)]. The behavior results in a sudden increase in fast-ion transport at a threshold that is well above the linear stability threshold for Alfven instability. A novel beam modulation technique [W. W. Heidbrink et al., Nucl. Fusion 56, 112011 (2016)], in conjunction with an array of fast-ion diagnostics, probes the transport by measuring the fast-ion flux in different phase-space volumes. Well above the threshold, simulations that utilize the measured mode amplitudes and structures predict a hollow fast-ion profile that resembles the profile measured by fast-ion D-alpha spectroscopy; the modelling also successfully reproduces the temporal response of neutral-particle signals to beam modulation. The use of different modulated sources probes the details of phase-space transport by populating different regions in phase space and by altering the amplitude of the AEs. Both effects modulate the phase-space flows. Published by AIP Publishing.

引用

页数：13

共 37 条

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