マルチスケールの不安定なカスケードからの磁気再接続

Auna L Moser¹, Paul M Bellan

¹Applied Physics, California Institute of Technology, Pasadena, California 91125, USA. auna@caltech.edu

Nature

|February 17, 2012

まとめ

磁気再接続率は,古典的なモデルが予測するよりも速い. この研究では,大規模な不安定性から小規模の (イオン皮膚の深さ) 不安定性へのカスケードが観察され,急速な再接続のダイナミクスを説明しています.

科学分野:

プラズマ物理学プラズマ物理学
天体物理学天体物理学
宇宙物理学宇宙物理学

背景:

磁気再接続は,宇宙や実験室でのプラズマ動力学にとって極めて重要です.
観測された再接続率は,古典的な抵抗性予測を上回る.
顕微鏡処理 (イオンラモール半径,イオン皮膚深度) が高速速度を説明することを提案されています.

研究の目的:

磁気再接続におけるマクロスケールからマイクロスケールへの移行を実証する.
マグネトヒドロダイナミックシステムがマイクロスケール物理にどのようにアクセスするかを説明する.
急速な磁気再接続の3次元ダイナミクスを解明するために.

主な方法:

磁気再接続を観察する実験室での実験.
不安定性の分析は,マクロスケールからマイクロスケールにカスケードする.
3次元プラズマダイナミクスの調査.

主要な成果:

マグネトヒドロダイナミックスケールからイオン皮の深さスケールまでの不安定性のカスケードが観察されました.
顕微鏡の電流シート薄めと顕微鏡の不安定性との関連が示されました.
再接続プロセスの完全な3次元ダイナミクスを解いた.

結論:

観測された不安定性のカスケードは,マクロスケールシステムがマイクロスケール物理学にアクセスし,迅速な再接続を行う方法を説明します.
これは,自然および実験用プラズマにおける再接続の衝動的な性質についての洞察を提供します.
この発見は,磁気水力力学理論と顕微鏡のプラズマの行動の間のギャップを埋めています.

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