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Updated: Apr 27, 2026
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アクティブな銀河です. NGC 5548の超大質量ブラックホールから,高速で長生きな流れが流れ出ている
J S Kaastra1, G A Kriss2, M Cappi3
1SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, Netherlands. Department of Physics and Astronomy, Universiteit Utrecht, Post Office Box 80000, 3508 TA Utrecht, Netherlands. Leiden Observatory, Leiden University, Post Office Box 9513, 2300 RA Leiden, Netherlands. j.kaastra@sron.nl.
Science (New York, N.Y.)
|July 5, 2014
まとめ
活発な銀河NGC 5548の新発見のガス流は,その核を大きく遮り,X線放射を遮断し,紫外線吸収を引き起こす. この急速な流出は,超大質量ブラックホールを取り巻く蓄積円盤から発生している可能性があります.
科学分野:
- 天文学と天体物理学について
- アクティブな銀河核 (AGN) 研究
- ブラックホール物理学 ブラックホール物理学
背景:
- 超大質量ブラックホール (SBHs) は,イオン化されたガスを放出することによって,活発な銀河に電力を供給します.
- NGC 5548は,原型活性銀河で,既知の持続的なイオン化された流出を示しています.
- 以前の研究では,X線と紫外線の観測を用いて,AGNの流出を特徴づけた.
研究 の 目的:
- 2013年の観測期間中にNGC 5548で観測された遮光現象を調査する.
- 新たに特定されたガス流の性質と起源を特徴付ける.
- この遮蔽ガスが活発な銀河核に与える影響を理解するために.
主な方法:
- 6つの宇宙観測所を使って観測を調整した.
- 高解像度X線と紫外線 (UV) のスペクトロスコピー.
- 放射される放射線に対する遮光効果の分析.
主要な成果:
- NGC 5548の核を遮る,長時間続く,塊状のイオン化されたガスの流れが検出されました.
- このガスは,柔らかいX線放射の約90%を遮断しました.
- 同時に深い,広い紫外線吸収の低谷が観察され,高い速度 (持続的な流出よりも最大5倍速く) を示しました.
結論:
- 新しく発見されたガス流は,NGC 5548.8の以前には観測されなかった重要な特徴を表しています.
- 高い流出速度と近さ (数光日) は,蓄積円盤からの起源を示唆しています.
- この発見は,活発な銀河核の複雑なダイナミクスと遮蔽メカニズムに関する新しい洞察を提供します.
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