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銀河の中心にある超大質量ブラックホール候補のイベントホライゾンスケール構造
Sheperd S Doeleman1, Jonathan Weintroub, Alan E E Rogers
1Massachusetts Institute of Technology (MIT) Haystack Observatory, Off Route 40, Westford, Massachusetts 01886, USA. sdoeleman@haystack.mit.edu
Nature
|September 5, 2008
まとめ
天文学者は,射手座A*を1.3mmで観測し,その内部直径がブラックホールのイベント地平線で予想されるよりも小さいことを明らかにしました. これは,放射がブラックホール自体からではなく,周囲の蓄積流から発生することを示唆しています.
科学分野:
- 天文学と天体物理学について
- ブラックホール物理学 ブラックホール物理学
- 銀河の核は銀河の核である.
背景:
- 超大質量ブラックホールは,物質を蓄積することによって,活発な銀河核を動かす.
- 射手座A* (Sgr A*) は,銀河系の中心に最も近い超大質量ブラックホールです.
- Sgr A*の近くの構造を解明することは,強い重力下での蓄積物理学の理解に不可欠です.
研究 の 目的:
- 射手座A*の周りの最も内側の増積流の構造を解明するために.
- 1.3mmの波長でSgr A*の固有の大きさを判別する.
- Sgr A*からの排出源を調査する.
主な方法:
- 1.3mmの波長で射手座A*の高解像度無線観測を行った.
- 観測されたデータを分析してSgr A*の内径を決定した.
- 観測された大きさを,ブラックホールのイベントホライゾンの予想される表面的な大きさと比較した.
主要な成果:
- 射手座A*の内部直径は37~+16~10マイクロ弧秒と測定されました.
- この測定された大きさは,ブラックホールの事象の地平線の予測された表面的な大きさよりも小さい.
- この発見は,放射がブラックホールに直接集中しているという仮定に異議を唱える.
結論:
- 射手座A*放射の大部分は,ブラックホール自体ではなく,周囲の蓄積流から発生している可能性があります.
- この研究は,超大質量ブラックホールの近くの蓄積過程に関する新しい制約を提供します.
- Sgr A*の排出メカニズムを完全に理解するには,さらなる研究が必要である.
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