The Excitation of Multiple Mode during the inter-ELM-crash Period in KSTAR H-mode Plasma

Abstract

The electron cyclotron emission imaging (ECEI) systems on KSTAR have been operated with quasi 3D view [1]. The temporal and spatial modulation of edge localized mode (ELM) structure has been observed during the inter-ELM-crash period in KSTAR discharge #7328 [2]. The observation is interpreted as simple superposition of two mode structure with different toroidal mode number. The modulation pattern is reproduced with the hypothesis that each mode can have different apparent rotation frequency. In addition, it is under investigation that the proposed multi-mode model could explain the observed fast mode number transition during the inter-ELM-crash period [3]. This work is supported by the NRF of Korea under Contract No. 2014M1A7A1A03029865. [1] G. S. Yun et al., Review of Scientific Instruments 85, 11D820 (2014) [2] M. Kim et al., "Multimode excitation during the inter-ELM-crash periods in KSTAR H-mode plasma", Nuclear Fusion (submitted) [3] Jieun Lee, "Changes of the toroidal mode number of the edge localized modes during ELM evolution in KSTAR plasma" ibid