太陽風の潜在的な源として,太陽活動領域の端から連続したプラズマの流出がある
Taro Sakao1, Ryouhei Kano, Noriyuki Narukage
1Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510, Japan. sakao@solar.isas.jaxa.jp
まとめ
科学者たちは,ヒノードX線望遠鏡を用いて,太陽の活発な領域からの熱プラズマの流出を観測した. 冠状孔の近くにあるこれらの流出は,太陽風の重要な源を代表し,その起源を特定するのに役立ちます.
科学分野:
- 太陽物理 太陽物理学
- プラズマ天体物理学とは
- ヘリオフィジックス ヘリオフィジックス
背景:
- 太陽は,イオン化された物質の流れである太陽風を宇宙に絶えず放出しています.
- 太陽風の正確な起源は,太陽圏環境への大きな影響にもかかわらず,ほとんど特定されていないままです.
研究 の 目的:
- 特定の太陽活動地域を観察することによって,太陽風の源を調査する.
- 太陽の表面からのプラズマ流出と,太陽風への潜在的貢献を分析する.
主な方法:
- Hinode X線望遠鏡からの観測を活用した.
- 冠状孔の隣接する太陽活動領域の軟X線放射プラズマパターンを分析した.
- 流出するプラズマの推定温度と密度.
主要な成果:
- 太陽活動領域の端にある開かれた磁場線に沿って,柔らかいX線を放射するプラズマの連続した流出を特定した.
- これらのアウトフローは,太陽風の総質量損失率のおよそ1/4に貢献すると推定されています.
- 上部コロナに広がるアウトフローが観察されました.
結論:
- 観測されたプラズマの流出は,太陽風の潜在的な源である.
- この発見は,冠状孔の近くの活発な地域からの太陽風の起源に関する新しい洞察を提供します.
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