An edge-coherent oscillation (ECO) with a bursting feature was observed in the steep-gradient pedestal region of H-mode plasmas in the HL-2A tokamak, where the type-I edge-localized modes (ELMs) were mitigated by application of n = 1 (n is the toroidal mode number) resonant magnetic perturbation (RMP). Utilizing a newly developed beam emission spectroscopy (BES) system, it was found that the ECO with a frequency of about 2 kHz is located at the edge pedestal region, and is excited by three-wave interaction of turbulence enhanced by the RMP field through the change of electron density gradient in the pedestal region because of the pump-out effect. The oscillation drives a significant outflow of particles as directly measured by probes, thus providing a channel for nearly continuous extra particle transport across the pedestal during ELM mitigation by RMP.

在HL-2A托卡马克的H型等离子体的陡峭梯度基座区域中观察到了具有爆裂特征的边缘相干振荡（ECO），其中通过应用I型边缘局限性模式（ELM）可以缓解这种情况。n = 1（n是环形模式数）共振磁扰动（RMP）。利用最新开发的光束发射光谱（BES）系统，发现频率约为2 kHz的ECO位于边缘基座区域，并受到RMP场通过湍流场增强的湍流的三波相互作用所激发。由于抽出效应，基座区域的电子密度梯度发生变化。振荡驱动大量的颗粒直接流出，直接由探针测量，从而为通过RMP减轻ELM过程中几乎连续的额外颗粒运输通过基座提供了通道。