高伝導性磁気水力ダイナミック渦巻におけるフローズ凍結分解
Gregory Eyink1, Ethan Vishniac, Cristian Lalescu
1Department of Applied Mathematics & Statistics, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, USA. eyink@jhu.edu
Nature
|May 24, 2013
まとめ
乱流リチャードソンアドベクションは,天体物理学プラズマにおける急速な磁気再接続に関する新しい説明を提供し,従来の伝統的な説明に異議を唱えます.
科学分野:
- プラズマ物理学のプラズマ物理学
- 天体物理学 天体物理学
- マグネトヒドロダイナミクス
背景:
- "凍結した"磁場線概念は,天体物理学現象を説明しますが,太陽フレアのような高導電性プラズマにおける急速な磁気トポロジーの変化を説明することはできません.
- マイクロ物理学的プラズマプロセスは,急速な再接続の説明として提案されていますが,大規模な天体物理学的スケールでの有効性は依然として不確実です.
研究 の 目的:
- 渦巻リチャードソンアドベクションが,天体物理学プラズマにおける大規模な磁気流構造の急速な再接続を説明できるかどうかを調査する.
- 流量凍結の分解を理解するために,磁気水力ダイナミックな乱流のシミュレーションを分析する.
主な方法:
- 高伝導性における磁気水力ダイナミック (MHD) 乱流のシミュレーションの分析.
- リチャードソン分散と磁場線運動に対するその影響を調査する.
主要な成果:
- シミュレーションはリチャードソンの分散を示し,乱流のアドベクションが磁場線を結びつける.
- この過程は"自発的にストキャスティック"な線運動につながり,イオン回転半径よりも大きなスケールで標準的な流量凍結を破る.
- 流体凍結の分解は,大規模な磁気構造の急速な再接続を説明する.
結論:
- 乱流リチャードソンアドベクションは,太陽フレアや冠状質量放出などの天体物理学現象における高速磁気再接続の実行可能な説明を提供します.
- このメカニズムは,蓄積円盤やガンマ線爆発を含む様々な天体物理学的文脈に適用できます.
- ストカスティックフックス凍結は,特定のプラズマフロー条件下での標準の凍結状態との急速な再接続を調和させます.
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