Speaker
Prof.
Hitoshi Tanaka
(Kyoto University)
Description
Non-inductive start-up of spherical tokamak (ST) is an important issue to realize compact and economical fusion reactors. In the Low Aspect ratio Torus Experiment (LATE) device, non-inductive start-up and formation of ST by electron Bernstein (EB) waves in a highly overdense regime has been explored. By injection of a 2.45 GHz microwave power of ~60 kW, the plasma current Ip is ramped up to ~12 kA and the electron density increases up to ~7 times the plasma cutoff density. Such a highly overdense ST plasma is produced by improved polarization adjustment for EB mode-conversion in the first propagation band. However, when Ip exceeds ~10 kA, Ip and the density become saturated. Intermittent plasma ejections across the last closed flux surface (LCFS) have been observed for the first time. Repetition of large ejection events causes saturation and gradual decrease of density and plasma current.
| Country or International Organisation | Japan |
|---|---|
| Paper Number | EX/P7-41 |
Primary author
Prof.
Hitoshi Tanaka
(Kyoto University)
Co-authors
Ms
Chiho Ikeda
(Kyoto University)
Mr
Kengoh Kuroda
(Kyoto University)
Mr
Kenichi Nagao
(Kyoto University)
Mr
Manato Wada
(Kyoto University)
Dr
Masaki Uchida
(Kyoto University)
Prof.
Takashi Maekawa
(Kyoto University)
Mr
Tatsuki Shigemura
(Kyoto University)
