銀河の中心にある超大質量ブラックホールの方向から急激にX線が発射される
F K Baganoff1, M W Bautz, W N Brandt
1Center for Space Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307, USA. fkb@space.mit.edu
Nature
|September 7, 2001
まとめ
射手座A* (Sgr A*) からの急速なX線フレアリングは,超大質量ブラックホールの有無の説得力のある証拠を提供します. この発見は,銀河の中心からの放出を推進するガス蓄積のモデルを支持する.
科学分野:
- 天体物理学 天体物理学
- 銀河系天文学 銀河系天文学
- ブラックホール物理学 ブラックホール物理学
背景:
- ほとんどの銀河は,核に超大質量ブラックホールを宿していると考えられています.
- 銀河系における恒星運動は,銀河の中心にある太陽の質量2.6×10^6の暗い天体を示唆しており,射手座A* (Sgr A*) と一致しています.
- Sgr A*からの放射は,ブラックホールへの物質の蓄積から発生すると仮定されていますが,特にX線では,その弱さは疑問を投げかけています.
研究 の 目的:
- 銀河の中心にあるコンパクト天体である Sagittarius A* (Sgr A*) の性質を調査する.
- 銀河の中心にある超大質量ブラックホールモデルに対する説得力のある証拠を,X線放射分析を通じて提供すること.
主な方法:
- 中央の暗黒天体の質量を決定するために,恒星運動の分析.
- Sgr A*の方向からの急速な発火を含むX線放射の観測と検出.
- 観測されたX線放射の相関関係と安定した放射と蓄積モデル.
主要な成果:
- Sgr A*の方向から発生する急速なX線フレアリングの発見.
- Sgr A*から以前報告された安定したX線放射の確認.
- 観測されたX線放射は,安定したものでも燃えるものでも,蓄積モデルを強く支持しています.
結論:
- Sgr A*からの急速なX線フレアリングは,銀河の中心にある超大質量ブラックホールの説得力のある証拠を提供します.
- この放射は,超大質量ブラックホールにガスが蓄積されていることと一致している.
- この発見は,銀河核におけるブラックホールの活動に関する理解を強化するものである.
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