マイクロクワザールGRS 1915+105のジェット抑制メカニズムとして,収縮円盤の風が吹いています
1Harvard University Department of Astronomy, 60 Garden Street, MS-10, Cambridge, Massachusetts 02138, USA. jneilsen@cfa.harvard.edu
Nature
|March 28, 2009
まとめ
GRS 1915+105のようなマイクロクワサーは,X線状態がはっきりしている. ジェットで照らされた蓄積円盤は,硬い状態では広い放射線を引き起こし,強力な風は,柔らかい状態ではジェットを抑制します.
科学分野:
- 天体物理学 天体物理学
- 高エネルギー天体物理学
- ブラックホール物理学 ブラックホール物理学
背景:
- 相対論ジェットを持つ恒星質量ブラックホールであるマイクロクワザールは,蓄積円盤の進化とジェット形成の研究に不可欠な研究室として機能しています.
- ブラックホールシステムにおけるジェット形成を誘発し抑制するメカニズムを理解することは,天体物理学における重要な課題です.
研究 の 目的:
- マイクロクワザールGRS 1915+105.5のジェット形成と抑制を制御する物理的プロセスを調査する.
- 観測されたスペクトル特性を,蓄積円盤とジェット活動と相関させる.
主な方法:
- マイクロクワザールGRS 1915+105.5からのX線放射の観測分析
- 幅広い放射線と狭い吸収線を特定するための光譜分析.
- スペクトル状態 (硬い,柔らかい) とジェットの存在と強さの相関.
主要な成果:
- 薄弱で硬い状態の広い放射線が検出され,内部の増積円盤のジェット照明に起因する.
- 強力な放射線による熱い風に関連した,明るい,柔らかな状態の狭い吸収線の観測.
- この風がラジオジェットへの質量流を大幅に減少させ,ジェット形成を効果的に抑制するという証拠があります.
結論:
- 観測されたスペクトル特徴は,蓄積円盤風と相対論ジェット生成の相互作用の直接的な証拠を提供します.
- この発見は,マイクロクワサールにおけるジェット活動のオン・オフを司るメカニズムを明らかにしている.
- GRS 1915+105は,活発な銀河核とクエザールにおけるジェットダイナミクスを理解するためのモデルシステムとして機能しています.
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