Two different threshold electric fields, characterizing a lower field required for significant seed RE generation and sustainment and a higher field required for the RE avalanche onset, have been experimentally observed in the flattop of EAST discharges. These results demonstrate that the threshold electric field for the RE avalanche onset is 1.2-fold higher than the RE detection onset field required for the primary generation. An updated 0-D model, including the delay in the RE avalanche onset, suggests that the RE population should be less than the previous prediction. The delay in the RE avalanche onset also opens a possibility for RE suppression at relatively low electron density.

中文翻译：

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托卡马克产生失控电子的两个阈值场的观测

已在 EAST 放电的平顶中通过实验观察到两种不同的阈值电场，其特征在于显着种子 RE 生成和维持所需的较低场和 RE 雪崩开始所需的较高场。这些结果表明，稀土雪崩开始的阈值电场比初级一代所需的稀土检测开始场高 1.2 倍。更新的 0-D 模型，包括 RE 雪崩开始的延迟，表明 RE 数量应该少于之前的预测。RE雪崩开始的延迟也为在相对低的电子密度下抑制RE提供了可能性。