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Updated: Jun 12, 2026
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Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
射手座Aのイベント地平線付近の磁場構造と変動の解明
Michael D Johnson1, Vincent L Fish2, Sheperd S Doeleman3
1Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA. mjohnson@cfa.harvard.edu.
Science (New York, N.Y.)
|January 20, 2016
まとめ
天文学者は,我々の銀河の中心にある超大質量ブラックホールである Sagittarius A* の近くで磁場を観測した. イベントホライズントの近くにある これらのフィールドは 部分的な順序と変性を示し ブラックホールの物理学の新たな洞察を 提供しています
科学分野:
- 天体物理学
- ブラックホール物理学
- マグネトヒドロダイナミック
背景:
- ブラックホールの周りの収縮円盤は 微分回転によって磁場を 増幅すると考えられています
- これらの増幅された磁場はシンクロトロン放出や相対論ジェット形成などの現象に不可欠です.
- 地平線スケールの磁場構造の観測証拠は不足している.
研究 の 目的:
- 射手座A*のイベント地平線近くの磁場構造を空間的に解明する.
- 超大質量ブラックホールの すぐ近くにある磁場の存在と性質を調査する
- これらの磁場の変性を検知し,特徴づけること.
主な方法:
- 1.3ミリ波長でのインターフェロメトリック観測を用いた.
- 射手座A*からの空間的に解明された線形偏振放射.
- イベントホライゾンのスケールで磁場特性を推測するためにデータを分析した.
主要な成果:
- Sagittarius A*のイベント地平線の近くで 部分的にオーダーされた磁場の証拠を検出しました
- シュワルツシルト半径6のスケールで 磁場を解明しました
- これらの磁場に関連した局所的な時間内変動.
結論:
- この発見は ブラックホールの近くの磁場発生と 増幅の理論を裏付けています
- オーダーされた磁場の観測証拠を horizont スケールで提供した.
- これらの磁場は,蓄積と流出のプロセスで重要な役割を果たすことを示唆しています.
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