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Updated: Jul 12, 2026

06:14
Simulating Imaging of Large Scale Radio Arrays on the Lunar Surface
Published on: July 30, 2020
アルフヴェン波は太陽のコロナにある
S Tomczyk1, S W McIntosh, S L Keil
1High Altitude Observatory (HAO), National Center for Atmospheric Research (NCAR), Post Office Box 3000, Boulder, CO 80307-3000, USA. tomczyk@ucar.edu
まとめ
アルフヴェン波は太陽のコロナで検出されましたが,観測された波は,冠状熱を説明するには弱すぎるようです. 未解明の波は,太陽の冠状の加熱メカニズムを理解する鍵を握っているかもしれない.
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:
- 太陽のコロナは数百万度に達し,現在のモデルでは完全に説明できない現象です.
- アルフヴェン波は,光球からコロナにエネルギーを輸送し,潜在的にこの加熱を誘導することを提案されています.
- 冠状熱の理解は,宇宙天候と地球への影響の予測に不可欠です.
研究 の 目的:
- 太陽のコロナにおけるアルフヴェン波を検知し,特徴づけること.
- 観測されたアルフヴェン波のエネルギー輸送能力を評価するため.
- 太陽の大気エネルギーバランスにおけるアルフヴェン波の役割を調査する.
主な方法:
- 国立太陽光天文台の冠状多チャンネル偏極計 (CoMP) を使いました.
- 太陽のコロナの強度,視線速度,線形極化データを分析した.
- FeXIII 1074.7ナノメートルの冠状放射線に焦点を当てました.
主要な成果:
- 太陽のコロナで,上向きに広がるアルフヴェン波が検出されました.
- 測定された波の相速度は,毎秒1〜4メガメートルの範囲です.
- 推論された波の軌道は,極化測定から得られた磁場方向と一致する.
結論:
- 検出された空間的に解明されたアルフヴェン波は,太陽のコロナを温めるのに不十分なエネルギーを運んでいます.
- 未解明のアルフヴェン波またはより小規模なアルフヴェン波が,冠状熱に必要なエネルギーを供給する可能性は残っています.
- 未解明の波群に関するさらなる調査は,冠状のエネルギー輸送を完全に理解するために必要である.
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