太陽光コンベクションゾーンの底辺のダイナミックな変動
Howe1, Christensen-Dalsgaard, Hill
1National Solar Observatory, National Optical Astronomy Observatories, Post Office Box 26732, Tucson, AZ 85726-6732, USA. Theoretical Astrophysics Center, Danish National Research Foundation, and Institute of Physics and Astronomy, Aarhus Uni.
Science (New York, N.Y.)
|March 31, 2000
まとめ
科学者たちは,太陽の底辺の回転の変化を観測し,低緯度では1.3年の変動を示した. これらの発見は,太陽ダイナモの洞察力を提供し,太陽の磁気活動のサイクルを潜在的に説明します.
科学分野:
- 太陽物理 太陽物理学
- ヘリオシズモロジー (ヘリオシズモロジー) とは
- 天体物理学 天体物理学
背景:
- 太陽の内部回転が磁気活動のサイクルに影響を与える.
- 旋回ダイナミクスを理解することは,太陽ダイナモのモデリングの鍵です.
- 以前の研究では,太陽の深い内部回転の詳細な測定が欠けていました.
研究 の 目的:
- 太陽の内部回転の時間的な変化を検知し,定量化するために.
- コンベクションと放射性ゾーンの境界であるタコクリンの近くの回転変動を調査する.
- 内部回転の変化と太陽ダイナモの関連性を探求する.
主な方法:
- 太陽の振動モードのほぼ継続的な観測を通じて,ヘリオ地震探査を利用する.
- データ取得のために,2つの互補する実験セットアップを使用します.
- グローバルモードの周波数分割を逆転させ,角速度 (オメガ) を決定する.
主要な成果:
- 太陽回転の有意な時間変化 (6nHzまで) がコンベクティブエンベロープの底辺の近くで検出されました.
- 低緯度での回転の顕著な1.3年周期変動が観察されました.
- 旋回の変化は,赤道と高緯度の近く,タコクリンの上下に最も顕著に見られました.
結論:
- 検出された回転の変動は,太陽力発電機が想定されている場所の近くで発生します.
- これらの変化は,タコクラインを横断する角速度の放射性梯度に相対して実質的です.
- 発見は,内部回転のダイナミクスと,太陽の22年間の磁気活動サイクルを生成するとの関連を示唆しています.
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