太陽の突出点における磁熱コンベクション
Thomas Berger1, Paola Testa, Andrew Hillier
1Lockheed Martin Advanced Technology Center, Solar and Astrophysics Laboratory, O/ADBS B/252, 3251 Hanover Street, Palo Alto, California 94304, USA. berger@lmsal.com
Nature
|April 15, 2011
まとめ
太陽の冠状腔内のより熱いプラズマバブルは浮力を提供し,レイリー-テイラー不安定性を引き起こします. これは,太陽の大気中の新しい磁熱コンベクション機構を明らかにし,冠状質量放出進化を説明します.
科学分野:
- 太陽物理 太陽物理学
- 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
背景:
- 冠状の穴は,磁気流のロープによって形成された,太陽の大気圏の大きい,低密度の領域です.
- これらの穴は進化し,冠状質量放出として噴火し,惑星の磁気圏に影響を与えます.
- 冠腔の進化のメカニズムは,未だに十分に理解されていない.
研究 の 目的:
- 冠状腔の極冠突起の内のプラズマ泡の性質と浮力を調査する.
- 噴火に向かう冠腔の進化におけるこれらの泡の役割を明らかにする.
- 太陽の突起と冠状の空洞に関する現在の水磁気概念に挑戦し,精錬する.
主な方法:
- 極冠突起の同時光学および極紫外 (EUV) 観測.
- 観測された"泡"と,その上にある突起材料内の血温度を分析する.
- 観測されたプラズマ特性の文脈でレイリー=テイラー不安定性を調査する.
主要な成果:
- 極冠の突出部内の観測されたバブルには,周囲の突出部 (2.5-12 × 10^5 K) よりも著しく熱いプラズマが含まれています.
- この温度差は,泡の浮力源となる.
- この発見は,冠状腔内の羽根形成のためのレイリー=テイラー不安定メカニズムを支持する.
結論:
- 冠状腔突起系は,新しい形の磁熱コンベクションを示している.
- より熱い浮遊性のあるプラズマバブルは,冠腔の進化と噴出を理解する鍵です.
- この研究は,太陽の突起と冠腔の既存の水磁気モデルに挑戦しています.
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