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arXiv · 1805.09594

The deteriorating effect of plasma density fluctuations on microwave beam quality

Alf Köhn·Max E. Austin·Michael W. Brookman·Kenneth W. Gentle·Lorenzo Guidi·Eberhard Holzhauer·Rob J. La Haye·Jarrod B. Leddy·Omar Maj·Craig C. Petty·Emanuele Poli·Terry L. Rhodes·Antti Snicker·Matthew B. Thomas·Roddy G. L. Vann·Hannes Weber
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Abstract

Turbulent plasma edge density fluctuations can broaden a traversing microwave beam degrading its quality. This can be a problem for scenarios relying on a high spatial localization of the deposition of injected microwave power, like controlling MHD instabilities. Here we present numerical estimations of the scattering of a microwave beam by density fluctuations over a large parameter range, including extrapolations to ITER. Two codes are used, the full-wave code IPF-FDMC and the wave kinetic equation solver WKBeam. A successful comparison between beam broadening obtained from DIII-D experiments and corresponding full-wave simulations is shown.

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Alf Köhn, Max E. Austin, Michael W. Brookman, Kenneth W. Gentle, Lorenzo Guidi, Eberhard Holzhauer, Rob J. La Haye, Jarrod B. Leddy, Omar Maj, Craig C. Petty, Emanuele Poli, Terry L. Rhodes, Antti Snicker, Matthew B. Thomas, Roddy G. L. Vann, Hannes Weber. 2018-05-24. The deteriorating effect of plasma density fluctuations on microwave beam quality. https://doi.org/10.1051/epjconf%2F201920301005

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