Comparison of Small Elm Characteristics and Regimes in Alcator C-mod, Mast, and Nstx
نویسندگان
چکیده
We report on the status of a set of ITPA-sponsored experiments among the Alcator C-Mod, MAST and NSTX devices to compare the characteristics and access conditions of small edge-localized modes (ELMs). Small ELM discharges were developed in each of the machines, and common features were identified, both in terms of ELM structure and operational windows. A common observation is an apparent βped threshold for small ELM access, although the absolute threshold value varied widely between the devices. In addition, most of the small ELM types had multiple filaments with propagation in the co-Ip direction.
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