EX/P6-19 Lower Hybrid and Electron Bernstein Wave Current Drive Experiments in MST
نویسنده
چکیده
Inductive current profile modification in MST has been successful in reducing fluctuations and transport but is transient and radially non-localized. Current profile control with rf waves offers steady and more precise control. Studies of lower hybrid wave and electron Bernstein wave injection are underway. The lower hybrid antenna has coupled 125 kW to the plasma. Hard x-ray emission with energies as high as 50 keV has been observed and the emission is spatially localized to the antenna location. A 250 kW system designed to heat electrons and drive current via the electron Bernstein wave is in operation at 3.6 GHz. Coupling studies performed with a phased-waveguide antenna have shown that the total power reflection coefficient can be maintained near 10%. X-ray production studies are in progress.
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