Observation of the Effects of Radially Sheared Electric Fields by the Use of a Gold Neutral Beam Probe

抄録

Intermittent turbulent potential fluctuations in ion-cyclotron wave heated plasmas and effects of their suppression due to strongly sheared plasma rotation with electron-cyclotron heating (ECH) for potential formation are observed in GAMMA 10. Such a shear effect on the central-cell potential data is demonstrated by the use of a heavy ion beam probe (HIBP) for the first time in GAMMA 10. The HIBP system with a gold neutral beam is employed for measuring profiles of radially formed potential as well as the associated radially sheared E_r in the central cell. During the application of ECH, the produced stronger E_r shear results in reduction of the turbulent fluctuations. The results are consistent with reported X-ray tomography data on the effect of E_r shear on turbulence suppression.