大幅のアルフヴェン波が太陽風を加熱し加速する場所での観測
Yeimy J Rivera1, Samuel T Badman1, Michael L Stevens1
1Center for Astrophysics, Harvard and Smithsonian, Cambridge, MA 02138, USA.
まとめ
パーカー・ソーラー・プローブとソーラー・オービターによって観測された大振幅のアルフヴェン波は,太陽風の加熱と加速に十分であることが判明し,以前の予想に異議を唱えた.
科学分野:
- 宇宙物理学
- プラズマ物理学
- ヘリオフィジックス
背景:
- 太陽風は太陽の冠を離れると加速し冷却しますが,自由に膨張するアディアバティックガスの予測よりも遅い速度です.
- アルフヴェン波は 惑星間磁場の乱れで エネルギーを運ぶことが知られています
研究 の 目的:
- 内部ヘリオスフィアの太陽風の加熱と加速におけるアルフヴェン波の役割を調査する.
- この地域を通過する宇宙船からの測定を分析する.
主な方法:
- パーカー・ソーラー・プローブと ソーラー・オービターによる 現場測定を用いて
- 特定の太陽風の流れを観測する 内部ヘリオスフィアを通過する
主要な成果:
- 観測により プラズマの加熱と加速が 確認されました
- 大幅のアルフェン波がこの地域内で検出されました.
- 観測された太陽風の現象は,これらの波のダッピングと機械的な働きによって十分に動いていることが示されました.
結論:
- アルフヴェン波のダッピングと機械的な作業は,内部ヘリオスフィアの急速な太陽風の加熱と加速を説明するのに十分です.
- この発見は太陽の近くで 太陽風の進化を推進する エネルギー伝達のメカニズムを提供する.
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