NGC 1365の中心にある,急速に回転している超大質量ブラックホール
G Risaliti1, F A Harrison, K K Madsen
1INAF-Osservatoria Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy. risaliti@arcetri.astro.it
Nature
|March 1, 2013
まとめ
活発な銀河の広いX線放射線は,ブラックホールの急速な回転を示唆しています. NGC 1365の新しいX線観測は,相対論的円盤特性を確認し,吸収のみモデルを排除し,ブラックホールの急速な回転をサポートしています.
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:
- 活発な銀河の広い鉄放射線は,ブラックホールの近くの蓄積円盤からの相対論的反射としてモデル化されることが多い.
- これらの線の歪みは,相対論的効果または間接吸収によるものと考えられており,ブラックホールのスピン決定に曖昧さをもたらしています.
- NGC 1365に関する以前の研究では,相対性反射モデルに基づいたブラックホールの急速な回転が示唆されていました.
研究 の 目的:
- 活性銀河NGC 1365のX線放射線の性質を調査する.
- 観測されたスペクトル特性を説明するための相対論的反射と吸収モデルを区別する.
- NGC 1365のブラックホールの急速な回転を確認または反論する.
主な方法:
- NGC 1365のX線観測の分析
- 吸収と反射による連続変化を区別するために時間とスペクトルの分析.
- 拡大したFe-K排出ラインとコンプトン散乱過剰の特定.
主要な成果:
- 拡大したFe-K放射線とコンプトン散乱過剰 (10-30 keV) を含む相対論円盤の特徴を観測した.
- 時間の変動による吸収を反射効果から解き放つことに成功した.
- ブラックホールの重力半径2.5以内から反射が発生することを決定した.
結論:
- この発見は,NGC 1365の相対論的円盤反射の有力な証拠を提供する.
- 吸収が優勢であるモデルは,統計的,物理的に排除されています.
- この結果は,NGC 1365の急速に回転するブラックホールの解釈を裏付けている.
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