Plasma Density Suppression by Electron Cyclotron Wave in Lower Hybrid Wave Driven TST-2 Spherical Tokamak Plasma

Abstract

For successful plasma current (Ip) ramp-up by the lower hybrid wave (LHW), the plasma density must be kept at a low level. In the TST-2 Ip ramp-up experiment using the LHW, the application of the electron cyclotron wave (ECW) was found to reduce the plasma density by about 10%. This allowed for further Ip ramp-up later in the discharge.