冠状の横断的な磁気水力ダイナミック波は,太陽の突出点にある
T J Okamoto1, S Tsuneta, T E Berger
1National Astronomical Observatory (NAOJ), Mitaka, Tokyo 181-8588, Japan. joten.okamoto@nao.ac.jp
Science (New York, N.Y.)
|December 8, 2007
まとめ
太陽の突起は,冷たいプラズマ雲である. 観測により,振動する構造はアルフヴェン波であり,太陽のコロナを潜在的に加熱していることが示唆されています.
科学分野:
- プラズマ物理学のプラズマ物理学
- 太陽系天体物理学 太陽系天体物理学
- マグネトヒドロダイナミクス
背景:
- 太陽の突起は,より冷たいプラズマ雲 (10^4 K) で,より熱い太陽のコロナ (10^6 K) の中に懸かっています.
- これらの突起を支え,コロナを熱させるメカニズムは,ほとんど未定のままである.
- 突起の内の微細な構造が観察されています.
研究 の 目的:
- 太陽の突出点における観測された微細構造の性質を調査する.
- 冠状熱におけるこれらの構造物の潜在的な役割を決定する.
- 突出振動と冠状磁場との関係を調査する.
主な方法:
- ヒノード衛星からの高解像度観測の分析.
- 空の平面で振動する糸状の構造に焦点を当てる.
- 磁場線の波伝達の文脈における振動の解釈.
主要な成果:
- 観測された細いスケールの糸状構造は,数分間の周期で振動を示す.
- これらの振動は,アルフヴェン波の伝播と一致しています.
- アルフヴェン波は,冠状磁場線に沿って移動する.
結論:
- 観測された振動は,アルフヴェン波を表している可能性が高い.
- これらのアルフヴェン波は,太陽のコロナの加熱に寄与する可能性がある.
- アルフヴェン波が冠状の加熱メカニズムに果たす役割を確認するためにさらなる研究が必要である.
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