POTENTIAL CONTROL FOR IMPROVEMENT OF CONFINEMENT IN THE GAMMA 10 TANDEM MIRROR

摘要

The central-cell density and diamagnetism have been doubled by a potential confinement. Thernduration of potential confinement has been extended from 50 ms to 100 ms. The potential distributionrnin the end region is studied in detail. Secondary electrons from end plates play an important role torndetermine the potential distribution. A mesh-bias experiment is underway to suppress the secondaryrnelectrons. The radial potential distribution in the central-cell is controlled by controlling potentialrndistributions of the end plates. The density fluctuation level is smaller when the radial electric field isrnlarger. However, the fluctuation level of drift wave turbulence is larger when the radial electric field isrnsmaller. The density increase by the potential confinement is larger when the anchor plates are floated.rnExperiments to apply bias potential to the anchor plates have been started.