FusionPapers
図版検索AI要約wiki日本の研究装置ジャーナルChatGPTAbout
© 2026 FUSIONPAPERS
About法務情報
トップに戻る

Information theory approach to plasma turbulence

Juan M López, José A Mier, Omar F Castellanos2026年6月Plasma Physics and Controlled FusionIF 2.2出版社

The nature of intermittency in turbulent plasma transport-whether bursts occur as independent events or exhibit memory-is a fundamental question with direct implications for confinement prediction and control. Conventional empirical time-series diagnostics, such as autocorrelation functions and power spectra, are second-order measures and, when used alone, may not fully characterize statistical dependence in intermittent, non-Gaussian plasma fluctuations dominated by nonlinear bursty avalanche-like events. Here we employ information-theoretic tools-block entropy, excess entropy, complexity index, and mutual information-to systematically probe temporal correlations in fluctuation-induced particle flux time series from the Santander Linear Plasma Machine. Experimental data are first converted into binary event/calm sequences via thresholding. Analysis of block entropy reveals that the complexity index grows with block length and remains unsaturated for the outermost radial positions, indicating significant temporal memory and structure. At the plasma edge, mutual information decays slowly and remains detectable over many consecutive bursty events, indicating that information propagates across the avalanche sequence far into the future. This provides a direct evidence that edge plasma turbulence exhibits non-renewal, long-range memory in burst occurrence: the timing of each large event contains predictive information about avalanches many events ahead. The complexity index and quiet-time mutual information together offer sensitive, model-free, quantitative markers of proximity to marginal stability and confinement regime transitions.

wiki

Plasma turbulence

AIによる論文要約

情報理論によるプラズマ乱流へのアプローチ
JAプラズマ物理研究者、乱流理論家、核融合実験者#プラズマ乱流 #情報理論 #間欠性 #相互情報量 #核融合
LLM向け: {"Title": "情報理論によるプラズマ乱流解析", "Authors": "著者不詳", "Research Objective": "プラズマ乱流の間欠…

プラズマ乱流における間欠的バーストが独立事象か記憶を持つかを調べるため、情報理論(ブロックエントロピー、過剰エントロピー、複雑性指数、相互情報量)を用いて粒子束の時系列を解析。実験データを閾値処理で2値化し、エッジプラズマではバースト間に長距離記憶があることを発見。相互情報量は遅く減衰し、情報が遠く未来まで伝播する。複雑性指数と静穏時間相互情報量は閉じ込め状態遷移の指標となる。

関連論文

Fast characterization of plasma states in W7-X with permutation entropy

2022Plasma Physics and Controlled Fusion

Propagation velocity of changes to confinement

2007Plasma Physics and Controlled Fusion

Causality detection and turbulence in fusion plasmas

2014Nuclear Fusion

Edge turbulence dynamics across electron–ion root transitions during ECRH modulation experiments in the TJ–II stellarator

2026Plasma Physics and Controlled Fusion

Transport analysis of transient phenomena in JET

1997Nuclear Fusion

Intermittency and extended self-similarity in space and fusion plasma: boundary effects

2008Plasma Physics and Controlled Fusion

Contribution of Tore Supra in preparation of ITER

2011Nuclear Fusion

Low frequency m = 1 modes during standard and improved confinement scenarios in W7-X

2025Nuclear Fusion

Dynamics of particle flux in a cylindrical magnetized plasma

2012Plasma Physics and Controlled Fusion

Nonlinear Magnetohydrodynamics

1998Nuclear Fusion