Electron Bernstein wave emission from an overdense reversed field pinch plasma

Abstract

Blackbody levels of emission in the electron cyclotron range of frequencies have been observed from an overdense (ωpe∼3ωce) Madison Symmetric Torus [Dexter et al., Fusion Technol. 19, 131 (1991)] reversed field pinch plasma, a result of electrostatic electron Bernstein waves emitted from the core and mode converted into electromagnetic waves at the extreme plasma edge. Comparison of the measured radiation temperature with profiles measured by Thomson scattering indicates that the mode conversion efficiency can be as high as ∼75%. Emission is preferentially in the X-mode polarization, and is strongly dependent upon the density and magnetic field profiles at the mode conversion point.