Gyrokinetic particle simulation of beta-induced Alfven-acoustic eigenmode

Journal Article · Fri Apr 15 00:00:00 EDT 2016 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.4947205· OSTI ID:22599131

Liu, Y. Q. ^[1]; Lin, Z. ^[2]; Zhang, W. L. ^[3]

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1. Fusion Simulation Center, Peking University, Beijing 100871 (China)
2. Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States)
3. Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

The beta-induced Alfven-acoustic eigenmode (BAAE) in toroidal plasmas is verified and studied by global gyrokinetic particle simulations. When ion temperature is much lower than electron temperature, the existence of the weakly damped BAAE is verified in the simulations using initial perturbation, antenna excitation, and energetic particle excitation, respectively. When the ion temperature is comparable to the electron temperature, the unstable BAAE can be excited by realistic energetic particle density gradient, even though the stable BAAE (in the absence of energetic particles) is heavily damped by the thermal ions. In the simulations with reversed magnetic shear, BAAE frequency sweeping is observed and poloidal mode structure has a triangle shape with a poloidal direction similar to that observed in tokamak experiments. The triangle shape changes the poloidal direction, and no frequency sweeping is found in the simulations with normal magnetic shear.

• OSTI ID: 22599131
• Journal Information: Physics of Plasmas, Vol. 23, Issue 4; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ANTENNAS
COMPARATIVE EVALUATIONS
DENSITY
ELECTRON TEMPERATURE
ELECTRONS
EXCITATION
ION TEMPERATURE
IONS
MAGNETIC FIELD CONFIGURATIONS
PARTICLES
PERTURBATION THEORY
PLASMA
REVERSED SHEAR
SIMULATION
TOKAMAK DEVICES