The first plasma discharges were successfully achieved on the experimental advanced superconducting tokamak (EAST) in 2006. The sawteeth behaviours were observed by means of soft x-ray diagnostics and ECE signals in the EAST. The displacement and radius of the q = 1 surface was studied and compared with the result of equilibrium calculation. The density sawtooth oscillation was also observed by the HCN laser interferometer diagnostics. The structure of the EAST operational region was studied in detail. Plasma performance was obviously improved by the boronization and wall conditioning. It was observed that lower qa and a wider stable operating region is extended by the GDC boronization.
EASTトカマクにおいて、初のプラズマ放電が2006年に成功した。軟X線診断およびECE信号により、EASTにおける鋸歯状振動（sawtooth）挙動が観測された。q=1面の変位と半径を測定し、平衡計算の結果と比較した。また、HCNレーザー干渉計による密度鋸歯状振動の観測も行われた。EASTの運転領域の構造が詳細に調査された。ボロン化と壁調整処理により、プラズマ性能が明らかに向上した。GDCボロン化によって、より低いq_a値とより広い安定運転領域が達成されることが観測された。