Radial electric field control by biased hot cathode in Tohoku University Heliac

Summary form only given, as follows. The influence of a negative biased electrode on the plasma parameters is investigated by using an emissive hot cathode made of LaB/sub 6/ in the Tohoku University Heliac. We have already succeeded in inducing the strong negative radial electric field by the negative biased hot cathode, which works as an electron source. In order to clarify the radial electric field formation in the heliac system, we attempted the following experiment, (i) radial current control with a constant current power supply, (ii) radial electric field control by the radial current.