Gyrokinetic Turbulence Investigations Involving Ion and Electron Scales

Plasma microinstabilities are one of the key physics problems on the way to efficient power plants based on nuclear fusion. They cause anomalous heat and particle transport which significantly degrades the plasma confinement quality, thus preventing self-sustaining plasma burning in present-day experiments. Hence, extensive experimental studies are dedicated to understanding and predicting turbulence features. They are accompanied by numerical simulations which are typically based on the gyrokinetic theory. While experimental diagnostics are about to address the role of fine-scale turbulence within a bath of large-scale turbulence, nonlinear gyrokinetic codes are already able to investigate turbulent transport at a wide range of wave numbers simultaneously. However, such simulations covering several space and time scales self-consistently are computationally extremely demanding and thus need to be massively parallelized.