Electron Bernstein wave heating via the slow X-B mode conversion process with direct launching from the high field side in LHD

Electron cyclotron heating (ECH) by electron Bernstein wave (EBW) excited by direct launching of the extraordinary (X-) mode from the high field side has been demonstrated for the first time in helical systems. In the large helical device (LHD), the X-mode can approach the upper hybrid resonance (UHR) layer directly through the ECR layer without installation of any additional mirror by oblique launching. Power absorption in the inner region occurred apart from the ECR layer with direct X-mode launching from the outer high field side of the ECR layer. It suggests EBW is excited and absorbed in the Doppler shifted ECR layer. (author)