ABSTRACT

In this article, partial and full collapses of sawtooth activity are investigated with the high-resolution two-dimensional electron cyclotron emission (ECE) Imaging diagnostic in EAST. The partial collapse in normal sawtooth behavior is detected during the precursor phase of an L-mode plasma heated by ICRF. The electron heat diffusivity is determined with the time-to-peak analysis. The experimental results revealed that heat diffusivity suppresses at the time of the partial collapse. As a result, the partial collapse process interrupts and the small amount of heat releases outward. The hot core survives and is enclosed by the cold magnetic island. The inversion radii are estimated with the help of sawtooth and the only single inversion radius is found during the entire collapse process.

摘要

在本文中，使用 EAST 中的高分辨率二维电子回旋发射 (ECE) 成像诊断研究了锯齿波活动的部分和完全崩溃。在由 ICRF 加热的 L 模式等离子体的前体阶段检测到正常锯齿行为的部分坍塌。电子热扩散率通过时间峰值分析确定。实验结果表明，热扩散率在部分坍塌时受到抑制。结果，部分坍塌过程中断，少量热量向外释放。热核幸存下来并被冷磁岛包围。在锯齿波的帮助下估计了反转半径，并且在整个坍塌过程中找到了唯一的单个反转半径。