Investigation of Plasma Behavior During the ECRH Injection in GAMMA 10

Electron Cyclotron Resonance Heating (ECRH) is used for the formation of the axial confining potential by plug/barrier-ECRH (P/B-ECRH) and for the bulk electron heating in the central-cell by central-ECRH (C-ECRH) in GAMMA 10. The plasma performance was increased with ECRHs injection. However the degradation of the plasma parameter was occasionally observed during C-ECRH injection. Increase of the number of the loss particle was also observed at the same time. The mechanism of the degradation of the plasma parameter was investigated in terms of the particle balance.