Author/Authors :
Nagasaki، نويسنده , , K and Isayama، نويسنده , , A and Zushi، نويسنده , , H and Sano، نويسنده , , F and Kondo، نويسنده , , K and Mizuuchi، نويسنده , , T and Besshou، نويسنده , , S and Okada، نويسنده , , H and Kurimoto، نويسنده , , Y and Funaba، نويسنده , , H and Hamada، نويسنده , , T and Kinoshita، نويسنده , , T and Obika، نويسنده , , T، نويسنده ,
Abstract :
Electron cyclotron emission (ECE) is measured with a multi-channel radiometer system in Heliotron-E. The system detects the second harmonic emission from 67 to 115 GHz at the magnetic field B = 1.9 T, covering the plasma confinement region up to the last closed flux surface. The radial and temporal evolution of the electron temperature has been obtained for electron cyclotron heated (ECH) and neutral beam injected (NBI) plasmas. Nonthermal electrons are observed at the plasma breakdown, and the nonthermal electron energy is estimated from the frequency downshift. We also discuss the effect of the magnetic shear on the second harmonic electron cyclotron wave propagating through the plasma with a strong magnetic shear such as heliotron/torsatron configurations.
