New Insights into Short-Wavelength, Coherent Edge Fluctuations
نویسندگان
چکیده
Two new tools have been employed to diagnose and actively perturb fluctuations in the edge plasma of the Alcator C-Mod tokamak. A mirror Langmuir probe [1, 2, 3] has been used to characterize edge fluctuations and transport with unprecedented detail. In addition, a new Shoelace antenna [4, 5] provides a direct drive to actively probe these fluctuations at a specific k⊥ (1.5 cm ) within a broad (45-300 kHz) frequency range. Both tools elucidate the physics associated with the Quasi-Coherent Mode (QCM, k⊥ = 1.5 cm , f = 50 − 200 kHz), the edge fluctuation responsible for the increased particle flux which sustains the steady-state, ELM-free Enhanced Dα (EDA) H-mode.
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تاریخ انتشار 2014