Investigation Of Electromagnetic Geodesic Acoustic Mode In East Rf-Heating Plasma

The magnetic fluctuations of geodesic acoustic modes (GAMs) have been investigated using a Doppler backscattering system and Mirnov probes during ion cyclotron resonance heating and lower hybrid wave heating in the edge plasma in the experimental advanced superconducting tokamak, and the magnetic component of the GAM was observed. The frequency of the GAM has a clear relationship with the edge electron temperature, and the mode numbers of the poloidal component of the magnetic structure of the GAM are approximately m = 2 (sin (2 theta)) and n = 0. A more detailed investigation shows that the maximum values of the amplitude of the poloidal magnetic field fluctuations and poloidal electric field fluctuations are approximately 10(-6) T and 200 V/m, respectively. Published by AIP Publishing.