冠状回路における滑り磁気再接続
Guillaume Aulanier1, Leon Golub, Edward E Deluca
1Observatoire de Paris, Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie (UPMC), Université Paris Diderot, 92190 Meudon, France. guillaume.aulanier@obspm.fr
Science (New York, N.Y.)
|December 8, 2007
まとめ
太陽フレアは磁気再接続によって引き起こされます. 新しい証拠は,磁場線が互いに滑り合う滑りやすい磁気再接続プロセスが,太陽フレアと冠状熱の理解の鍵であることを示唆しています.
科学分野:
- プラズマ物理学のプラズマ物理学
- 太陽物理 太陽物理学
- 天体物理学 天体物理学
背景:
- 太陽の冠状回路における磁気再接続は,太陽フレアと冠状熱を誘発する.
- 標準モデルは,断続的な磁場マッピングにおいて,瞬時の磁場線断裂を想定している.
- 別の滑り磁気再接続モードは,連続するが急なフィールドグラデーションで発生する可能性があります.
研究 の 目的:
- 太陽のコロナにおける磁気再接続の滑落の存在と影響を調査する.
- 滑り磁気再接続モデルに観測的サポートを提供するために.
- 太陽光および実験用プラズマにおける磁気再接続の解釈を参考にするために.
主な方法:
- ヒノード宇宙船からの柔らかいX線観測の分析.
- 冠状回路の急速な双方向運動の観測.
- 観測された現象と磁気再接続の理論的モデルを比較する.
主要な成果:
- 冠状回路の観測された高速双方向運動は,滑りやすい磁気再接続の証拠を提供します.
- このレジムは,磁場マッピングが連続しているが,急な傾斜がある場合に動作します.
- 標準的な即時再接続モデルに代わるものをサポートします.
結論:
- 滑りやすい磁気再接続は,太陽のコロナで実行可能なプロセスです.
- このメカニズムは,太陽フレアや冠状熱を研究する際に考慮されるべきです.
- この発見は,太陽光と実験室でのプラズマ再接続研究の両方にとって重要である.
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