The repetitive locking-unlocking process of a large ##IMG## [http://ej.iop.org/images/0741-3335/62/9/094002/ppcfab9b3bieqn1.gif] {$m/n = 2/1$} neoclassical tearing mode (NTM) is studied on the DIII-D tokamak. Cyclical periods of partial suppression are achieved when β p and the expected bootstrap current ##IMG## [http://ej.iop.org/images/0741-3335/62/9/094002/ppcfab9b3bieqn2.gif] {$J_{\mathrm{BS}}$} drop upon back-transitions to L-mode. Diminished L-mode bootstrap current is required to explain decreased island size as modeled by the generalized Rutherford equation. At EC power levels too low to fully suppress the NTM, partial suppression is enough to reduce the torque on the mode to the point where viscous drag from the background plasma overcomes the electromagnetic torque and restores fast plasma rotation and H-mode. Additional current drive is shown to further reduce the size of the mode until full suppre...

中文翻译：

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DIII-D锁模期间基于电子回旋电流驱动的新古典撕裂模式抑制阈值降低的实验证据

大型## IMG ##的重复锁定-解锁过程[http://ej.iop.org/images/0741-3335/62/9/094002/ppcfab9b3bieqn1.gif] {$ m / n = 2/1在DIII-D托卡马克上研究了新古典撕裂模式（NTM）。当βp和预期的自举电流## IMG ## [http://ej.iop.org/images/0741-3335/62/9/094002/ppcfab9b3bieqn2.gif] {$ J_ {\ mathrm {BS}} $}在向后转换为L模式时会下降。需要用L模式自举电流减小来解释减小的岛尺寸，这是由广义Rutherford方程建模的。在EC功率水平太低而无法完全抑制NTM的情况下，部分抑制足以将模式上的扭矩减小到这样的程度：从背景等离子体中产生的粘性阻力克服了电磁扭矩，并恢复了快速的等离子体旋转和H模式。