空間的に解明された磁気編み物から太陽のコロナにエネルギーが放出されます
J W Cirtain1, L Golub, A R Winebarger
1Marshall Space Flight Center, NASA, Mail Code ZP13, MSFC, Alabama 36812, USA. jonathan.w.cirtain@nasa.gov
Nature
|January 25, 2013
まとめ
太陽のコロナにおける磁気再接続により,プラズマはケルビン数百万度まで加熱されます. 新しい高解像度観測により,新冠に微細な磁気編み物があることが明らかになり,この加熱メカニズムの証拠となる.
科学分野:
- ソーラー物理学 ソーラー物理学
- プラズマ天体物理学とは
- マグネトヒドロダイナミクス
背景:
- 太陽の外側の大気圏 (コロナ) はかなりの加熱を必要とし,1.5~400万ケルビンの温度に達します.
- 静かな太陽光期には波熱が提案されていますが,活発な地域には追加のエネルギー源が必要です.
- 編み物磁場線の磁気再接続は,アクティブコロナ加熱の主要な理論的候補である.
研究 の 目的:
- 太陽のコロナにおける加熱メカニズムとしての磁気編み物と再接続に関する観測的証拠を提供する.
- これまでに観測されていなかった,コロナの微細な磁気構造を解明するために.
- 観測された磁気再接続イベントによって放出されたエネルギーを定量化するために.
主な方法:
- 太陽活動地域を高解像度で撮影し,角解像度は0.2弧秒である.
- コロナ内の微細な磁気編み物の観察と分析.
- 磁場再接続,リラクゼーション,エネルギー消耗のプロセスを監視する.
主要な成果:
- 太陽のコロナで微細な磁気編み物 (0.2弧秒) を直接観測する.
- これらの織りなされた磁気構造の再接続と緩和の証拠です.
- 観測されたエネルギー分散は,冠状のプラズマを約400万ケルビンまで加熱するのに十分である.
結論:
- 細いスケールのブレイドの磁気再接続は,活発な太陽のコロナを加熱するための実行可能なメカニズムです.
- フィールドのリラックスから観測されたエネルギー放出は,高温を説明するのに十分です.
- このメカニズムがすべての活性地域における支配的な加熱プロセスであることを確認するために,さらなる観測が必要である.
関連する概念動画
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