ブラックホールの蓄積円盤からの風は,活発な銀河の分子流出を駆動する
F Tombesi1, M Meléndez2, S Veilleux3
11] X-ray Astrophysics Laboratory, NASA/Goddard Space Flight Center, Greenbelt, Maryland 20771, USA [2] Department of Astronomy and CRESST, University of Maryland, College Park, Maryland 20742, USA.
Nature
|March 27, 2015
まとめ
科学者たちは,超明るく輝く銀河で強力な蓄積円盤風を検知し,クエーザーのフィードバックメカニズムを確認した. この発見は,超大質量ブラックホールの活動と銀河の進化を結びつけ,風が恒星形成を抑制する方法を説明します.
科学分野:
- * 天体物理学
- *銀河進化の進化について
- * ブラックホール物理学
背景:
- * 活発な銀河核 (AGN) 風は,銀河の進化と超大質量ブラックホールの成長を調節すると理論化されています.
- * 超明るい赤外線銀河 (ULIRG) は分子外流を示し,クエーサーフィードバック仮説を支持する.
- * 過去の研究では,ULIRGにおける大規模な分子流出と蓄積円盤風を結びつける直接的な証拠が欠けていた.
研究 の 目的:
- * 既知の分子流出量を持つULIRGにおける蓄積円盤風を検知し,特徴づけること.
- * クワザールフィードバックの提案されたエネルギー節約メカニズムに関する観測的証拠を提供するため.
- * 恒星形成の消火などの銀河全体の現象とAGN活動を結びつける.
主な方法:
- * 近くのULIRG IRAS F11119+3257.7のX線スペクトロスコピーを撮影しました.
- *相対論的な風のサインを特定するために,スペクトルデータの分析.
- * アウトフローエネルギーとクワザールフィードバックの理論モデルを比較.
主要な成果:
- * IRAS F11119+3257.7.で軽度の相対論速度 (0.25c) を有する強力な蓄積円盤風が検出されました.
- *IRAS F11119+3257のAGNはクエーザーのような明るさ (1.5 × 10^46 erg/s) を表しています.
- * 検出された蓄積円盤風と銀河の分子流出のエネルギーは,エネルギー保存フィードバックメカニズムと一致しています.
結論:
- *この研究は,分子流出を伴うULIRGにおける増積円盤風の直接検出を初めて可能にしました.
- * これは,強力なラジオジェットがない銀河のクワザールフィードバックプロセスにおけるAGN駆動風の役割を確認しています.
- *この発見は,超大質量ブラックホールの活動と宿主銀河の恒星形成の調節との関連性を強化している.
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