A new branch of the m/n = 2/1 fishbone-like mode is found to be excitated by trapped energetic ions when the tearing mode is unstable. An energy-principle-based dispersion relation is derived and analyzed, which incorporates the wave-particle resonance and the resistive layer physics. Once the beta amplitude of trapped energetic ions exceeds a critical value, 2/1 fishbone-like instabilities would appear. The mode transition from tearing mode to 2/1 fishbone-like mode will be triggered with the increasing beta of trapped energetic ions. The total effects of the ideal magnetohydrodynamic potential energy and the adiabatic contribution of trapped energetic ions on the real frequency and growth rate of 2/1 fishbone-like modes are investigated; the effects of magnetic Reynolds number and magnetic shear are also studied. Both resistivity and magnetic shear play a stable role on 2/1 fishbone-like modes. An implication of the theory is conducive to understanding the 2/1 fishbone-like ac...

中文翻译：

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捕获的高能离子激发2/1鱼骨状模式

当撕裂模式不稳定时，m / n = 2/1鱼骨样模式的新分支被捕获的高能离子激发。导出并分析了基于能量原理的色散关系，该关系包含了波粒共振和电阻层物理原理。一旦捕获的高能离子的贝塔振幅超过临界值，就会出现2/1鱼骨状的不稳定性。从捕获的高能离子的β增大，将触发从撕裂模式到2/​​1鱼骨样模式的模式转换。研究了理想的磁流体动力势能和被困的高能离子的绝热贡献对2/1鱼骨状模态的真实频率和增长率的影响。还研究了雷诺数和磁剪切的影响。电阻率和磁剪切力在2/1鱼骨状模式中均起稳定作用。该理论的含义有助于理解2/1鱼骨状的...