Department of Mechanical Engineering and Manufacturing, University of Seville, Camino de los Descubrimientos s/n, 41092 Seville, Spain.
Department of Physics and Astronomy, University of California, Irvine, California 92697, USA.
Phys Rev Lett. 2023 Jan 20;130(3):035101. doi: 10.1103/PhysRevLett.130.035101.
The suppression and excitation of Alfvén eigenmodes have been experimentally obtained, for the first time, by means of externally applied 3D perturbative fields with different spatial spectra in a tokamak plasma. The applied perturbation causes an internal fast-ion redistribution that modifies the phase-space gradients responsible for driving the modes, determining, ultimately their existence. Hybrid kinetic-magnetohydrodynamic simulations reveal an edge resonant transport layer activated by the 3D perturbative field as the responsible mechanism for the fast-ion redistribution. The results presented here may help to control fast-ion driven Alfvénic instabilities in future burning plasmas with a significant fusion born alpha particle population.
首次在托卡马克等离子体中通过施加具有不同空间谱的外部三维微扰场，实验获得了阿尔文本征模的抑制和激发。所施加的微扰引起内部快离子再分布，从而改变了驱动模式的相位空间梯度，最终决定了模式的存在。混合动理学-磁流体动力学模拟揭示了由三维微扰场激活的边缘共振输运层，这是导致快离子再分布的原因。这里提出的结果可能有助于在具有显著聚变产生阿尔法粒子的未来燃烧等离子体中控制快离子驱动的阿尔文不稳定性。
