{beta}-Induced Alfven Eigenmodes Destabilized by Energetic Electrons in a Tokamak Plasma

Journal Article · Fri Oct 29 00:00:00 EDT 2010 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.105.185004· OSTI ID:21467055

Chen, W; Ding, X T; Yang, Q W; Liu, Yi; Ji, X Q; Zhang, Y P; Zhou, J; Yuan, G L; Sun, H J; Li, W; Zhou, Y; Huang, Y; Dong, J Q; Feng, B B; Song, X M; Shi, Z B; Liu, Z T; Song, X Y; Li, L C; Duan, X R ^[1]

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1. Southwestern Institute of Physics, P.O. Box 432 Chengdu 610041 (China)

The {beta}-induced Alfven eigenmode (BAE) excited by energetic electrons has been identified for the first time both in the Ohmic and electron cyclotron resonance heating plasma in HL-2A. The features of the instability, including its frequency, mode number, and propagation direction, can be observed by magnetic pickup probes. The mode frequency is comparable to that of the continuum accumulation point of the lowest frequency gap induced by the shear Alfven continuous spectrum due to finite {beta} effect, and it is proportional to Alfven velocity at thermal ion {beta} held constant. The experimental results show that the BAE is related not only with the population of the energetic electrons, but also their energy and pitch angles. The results indicate that the barely circulating and deeply trapped electrons play an important role in the mode excitation.

• OSTI ID: 21467055
• Journal Information: Physical Review Letters, Vol. 105, Issue 18; Other Information: DOI: 10.1103/PhysRevLett.105.185004; (c) 2010 American Institute of Physics; ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ALFVEN WAVES
BUILDUP
ECR HEATING
EXCITATION
HL-2 TOKAMAK
IONS
PLASMA
PLASMA INSTABILITY
SHEAR
TAIL ELECTRONS
TRAPPED ELECTRONS
CHARGED PARTICLES
CLOSED PLASMA DEVICES
ELECTRONS
ELEMENTARY PARTICLES
ENERGY-LEVEL TRANSITIONS
FERMIONS
HEATING
HIGH-FREQUENCY HEATING
HYDROMAGNETIC WAVES
INSTABILITY
LEPTONS
PLASMA HEATING
THERMONUCLEAR DEVICES
TOKAMAK DEVICES