RMP Island Measurements and Optimizations
2025 Research Campaign, Transient Control
Purpose of Experiment
This study aims to achieve the decisive direct measurement of pedestal-top island formation during resonant magnetic perturbation (RMP) driven edge-localized mode (ELM) suppression in the DIIID tokamak. Understanding this phenomenon is crucial for validating the hypothesis that pedestal-top islands limit pedestal growth, preventing peeling-ballooning instabilities.
Experimental Approach
By leveraging high-resolution diagnostics, including Thomson scattering, HRECE, ECEI, BES, and edge reflectometry, the experiment seeks to isolate the island response from 3D kink structures using rotating RMPs and hysteresis techniques. The findings will enhance the robustness of RMP-ELM modeling, improving predictive capabilities for ITER and future fusion devices. Additionally, a new rt-TORBEAM will be employed to optimize EC, ensuring robust and reliable ELM suppression. The results of this experiment will provide critical insights into ELM control physics and inform the development of effective strategies for plasma stability in next-generation reactors.
See more details, including project leads, at U.S. Department of Energy, Office of Scientific and Technical Information (OSTI).