Multidimensional Visualization of MHD and Turbulence in Fusion Plasmas

Quasi-optical imaging at sub-THz frequencies has a major impact on fusion plasma diagnostics. Millimeter-wave imaging reflectometry utilizes microwaves to actively probe fusion plasmas, inferring the local properties of electron density fluctuations. Electron cyclotron emission imaging is a multichannel radiometer that passively measures the spontaneous emission of microwaves from the plasma to infer local properties of electron temperature fluctuations. These imaging diagnostics work together to diagnose the characteristics of turbulence and magnetohydrodynamic activity. Important quantities, such as amplitude and wavenumber of coherent fluctuations, correlation lengths and decorrelation times of turbulence, and poloidal flow velocity of the plasma, are readily inferred.