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Indexed by:期刊论文

Date of Publication:2018-02-01

Journal:PLASMA SCIENCE & TECHNOLOGY

Included Journals:SCIE、EI、CPCI-S

Volume:20

Issue:2

ISSN No.:1009-0630

Key Words:post-cursor mode; H-mode; small ELM

Abstract:A 'post-cursor' quasi-coherent mode with frequency similar to 50 kHz has been observed following the crash of small edge localized modes (ELMs) in the Experimental Advanced Superconducting Tokamak by using a reciprocating Langmuir probe system inserted at the outboard midplane. This mode with strong potential and magnetic perturbations propagates in the electron-diamagnetic drift direction in the laboratory frame. In addition, these quasi-coherent fluctuations appear to be modulated by a MHD mode with lower frequency (similar to 5 kHz). The bi-coherence analysis shows that the post-cursor mode and the MHD mode have nonlinear interaction through three-wave coupling. The understanding on post-cursor mode can enhance our knowledge of ELMs and pedestal physics, and give new insight into the ELM process itself.