PHYSICS OF GASES, PLASMAS, AND ELECTRIC DISCHARGES
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Energetic Particle Physics on the HL-2A Tokamak: A Review
Pei-Wan Shi1,2, Wei Chen1*, and Xu-Ru Duan1
1Southwestern Institute of Physics, Chengdu 610041, China 2Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams (Ministry of Education), School of Physics, Dalian University of Technology, Dalian 116024, China
Cite this article:
Pei-Wan Shi, Wei Chen, and Xu-Ru Duan 2021 Chin. Phys. Lett. 38 035202
Abstract Interaction between shear Alfvén wave (SAW) and energetic particles (EPs) is one of major concerns in magnetically confined plasmas since it may lead to excitation of toroidal symmetry breaking collective instabilities, thus enhances loss of EPs and degrades plasma confinement. In the last few years, Alfvénic zoology has been constructed on HL-2A tokamak and series of EPs driven instabilities, such as toroidal Alfvén eigenmodes (TAEs), revered shear Alfvén eigenmodes (RSAEs), beta induced Alfvén eigenmodes (BAEs), Alfvénic ion temperature gradient (AITG) modes and fishbone modes, have been observed and investigated. Those Alfvénic fluctuations show frequency chirping behaviors through nonlinear wave-particle route, and contribute to generation of axisymmetric modes by nonlinear wave-wave resonance in the presence of strong tearing modes. It is proved that the plasma confinement is affected by Alfvénic activities from multiple aspects. The RSAEs resonate with thermal ions, and this results in an energy diffusive transport process while the nonlinear mode coupling between core-localized TAEs and tearing modes trigger avalanche electron heat transport events. Effective measures have been taken to control SAW fluctuations and the fishbone activities are suppressed by electron cyclotron resonance heating. Those experimental results will not only contribute to better understandings of energetic particles physics, but also provide technology bases for active control of Alfvénic modes on International Thermonuclear Experimental Reactor (ITER) and Chinese Fusion Engineering Testing Reactor (CFETR).
Received: 27 November 2020
Published: 02 March 2021
(Nonlinear phenomena: waves, wave propagation, and other interactions (including parametric effects, mode coupling, ponderomotive effects, etc.))
Fund: Supported by the National Key R&D Program of China (Grant Nos. 2019YFE03020000 and 2017YFE0301200), the National Natural Science Foundation of China (Grant Nos. 11835010, 11875021 and 11875024), and the China Postdoctoral Science Foundation (Grant No. 2020M670756).