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Modifications of plasma edge electric field and confinement properties by limiter biasing on the KT-5C tokamak

Published online by Cambridge University Press:  13 March 2009

Hui Gao
Affiliation:
Department of Modern Physics, University of Science and Technology of China, Hefei, 230027, China
Kan Zhai
Affiliation:
Department of Modern Physics, University of Science and Technology of China, Hefei, 230027, China
Yi-Zhi Wen
Affiliation:
Department of Modern Physics, University of Science and Technology of China, Hefei, 230027, China
Shu-De Wan
Affiliation:
Department of Modern Physics, University of Science and Technology of China, Hefei, 230027, China
Chang-Xun Yu
Affiliation:
Department of Modern Physics, University of Science and Technology of China, Hefei, 230027, China

Abstract

Experiments using a biased multiblock limiter in the KT-5C tokamak show that positive biasing is more effective than negative biasing in modifying the edge electric field, suppressing fluctuations and improving plasma confinement. The biasing effect varies with the limiter area, the toroidal magnetic field and the biasing voltage. By positive biasing, the edge profiles of the plasma potential, the electron temperature and the density become steeper, resulting in a reduced edge particle flux, an increased global particle confinement time and lower fluctuation levels of the edge plasma.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1995

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