München 2019 – wissenschaftliches Programm
P 18.60: Poster
Donnerstag, 21. März 2019, 16:30–18:30, Foyer Audimax
Partial Mutual Information analysis of spatio-temporal ECE data in W7-X — •Juan Fernando Guerrero Arnaiz2, Andreas Dinklage1,2, Bernd Pompe2, Matthias Hirsch1, Udo Hoefel1, Robert Wolf1, and The W7-X Team1 — 1Max-Planck-Institute for Plasma Physics, 17491 Greifswald, Germany — 2University of Greifswald, 17489 Greifswald, Germany
Quantifying the spatio-temporal behavior of fluctuating quantities may reveal transport characteristics in high temperature plasmas. Traditional techniques employ cross correlations or higher-order statistics to determine relevant space and time scales as well as propagation velocities of the perturbations displayed by the diagnostic signals. Here we implement partial mutual information analysis on plasma data, which gives additional insight on the spatio-temporal coupling of observations at different locations. Specifically, time series from electron cyclotron emission (ECE) at different cyclotron frequencies, representing different locations along the diagnostic sightline in Wendelstein 7-X are analyzed. The technique allowed for the characterization of coupling of different observations on the same flux surface and thereby the identification of measurements supposed to originate from symmetric plasma profiles. Differently to other methods, partial mutual information analysis allows one to study the effect of spurious signal contributions, like common drivers of the signals under comparison. This capability may finally serve for causality detection.