Phase-Space Pattern Extraction from 5D gyrokinetic simulation data

Asahi, Yuichi   ; Fujii, Keisuke*; Maeyama, Shinya*; Idomura, Yasuhiro   

We propose to use a dimensionality reduction technique, namely principal component analysis (PCA) to extract patterns from the series of 5D gyrokinetic plasma simulation data. It is shown that 83% of the variance of the original 6D (5D phase space + 1D time) data can be expressed with 64 principal components. Through the detailed analysis of the contribution of each principal component to the energy flux, we demonstrate that the avalanche like energy transport is driven by coherent mode structures in the phase space, indicating the key role of resonant particles.