The effect of bootstrap current perturbation on the onset of neoclassical tearing modes (NTMs) is studied numerically based on two-fluid equations, using externally applied resonant magnetic perturbations (RMPs) as triggers. With increasing the bootstrap current density, a larger RMP is found to be required to excite the NTM's onset when the bi-normal electron fluid velocity is in the ion drift direction, being contrary to the conventional understanding that the bootstrap current perturbation is always destabilizing. For the electron fluid velocity in the electron drift direction, however, the opposite results are found.

中文翻译：

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自举电流对新古典撕裂模式开始的影响

使用外部施加的共振磁扰动 (RMP) 作为触发器，基于双流体方程对自举电流扰动对新古典撕裂模式 (NTM) 开始的影响进行了数值研究。随着自举电流密度的增加，发现当双法向电子流体速度在离子漂移方向时需要更大的 RMP 来激发 NTM 的开始，这与自举电流扰动总是不稳定的传统理解相反。然而，对于电子漂移方向上的电子流体速度，发现了相反的结果。