地球の渦巻磁気層におけるイオン結合なしの電子磁気再接続
T D Phan1, J P Eastwood2, M A Shay3
1Space Sciences Laboratory, University of California, Berkeley, CA, USA. phan@ssl.berkeley.edu.
Nature
|May 11, 2018
まとめ
科学者は地球の磁気殻に 電子ジェットを観測し 新しい磁気再接続の形を明らかにしました このプロセスは,イオンカップリングなしで小規模な電流シートで渦巻のエネルギー転送を駆動します.
科学分野:
- プラズマ物理学
- 宇宙物理学
- 天体物理学
背景:
- 磁気再接続は磁気エネルギーを 粒子エネルギーに変換します これは宇宙や実験室の プラズマに不可欠です
- 標準モデルは電子スケールの拡散領域での再接続を記述し,その後にイオンジェットが続きます.
- 運動スケールでの渦巻性プラズマエネルギー分散における再接続の役割は理論化されているが,観測証拠は欠けている.
研究 の 目的:
- 磁気再接続とプラズマジェットを小規模な渦巻プラズマで調査する.
- 地球の磁殻との再接続の 観測証拠を提供するためです
- 標準的なイオン結合噴射を超えた代替再接続モデルを探求する.
主な方法:
- 地球の渦巻磁気層の電子スケールの電流シートの現地観測.
- 磁場,電場,粒子エネルギー化に関する分析
- 標準および代替再接続モデルとの観測の比較
主要な成果:
- 電子スケールの電流シートの中で 二方向の超イオンアルフェニック電子ジェットが検出されました
- 観測された平行電場と 磁気から粒子へのエネルギー変換の強化
- イオンジェットや 広範囲の電流層は 見つかりませんでした 標準モデルと矛盾しています
結論:
- この研究は,小規模な渦巻性プラズマにおける再接続プラズマジェットの最初の観測証拠を示しています.
- イオン結合のない電子ジェットによって駆動される新しい再接続形態が特定されました.
- この電子スケール再接続メカニズムは,宇宙プラズマの渦巻エネルギー転送と分散に寄与します.
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