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天体物理学的蓄積円盤における特徴的な光学的変動時間尺度
Colin J Burke1,2, Yue Shen3,4, Omer Blaes5
1Department of Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
Science (New York, N.Y.)
|August 13, 2021
まとめ
研究者は67の活発な銀河核で 光学的な変動性を研究しました 彼らは変化の時間スケールとブラックホールの質量との相関性を発見し,様々なスケールに共通する蓄積円盤のプロセスを示唆しました.
科学分野:
- 天体物理学
- ブラックホール物理学
- アクレションディスクダイナミクス
背景:
- アクティブな銀河核 (AGN) は,超大質量ブラックホールの周りの蓄積円盤を特徴としています.
- これらの円盤は紫外線と光学放射線を放射し,蓄積フローの物理によりストキャスティックな変動を示します.
- 変動時間スケールを理解することは,蓄積円盤の性質を調査するために重要です.
研究 の 目的:
- 67の活性銀河核のサンプルで 光学連続体の可変性を測定する
- 変動力のスペクトルが平らになる特徴的な時間スケールを特定します.
- この時間スケールとブラックホールの質量との関係を調べるため
主な方法:
- 67の活発な銀河核の光学フォトメトリック監視
- 光の曲線を分析し,波動力のスペクトルを決定する.
- 各 AGN の特徴的な平らな時間スケールの計算.
主要な成果:
- 超大質量ブラックホールの幅広い範囲で,変動時間スケールとブラックホールの質量との間に有意な相関が発見されました.
- 観測された時間スケールは,標準の蓄積円盤モデルにおける紫外線放射半径における熱時間スケールの理論的予測と一致する.
- アクレートする白矮星は類似の行動を示し,統一された蓄積円盤のプロセスを示唆している.
結論:
- この研究は,蓄積円盤の変動時間スケールとAGNのブラックホールの質量との間に堅固な相関を確立しています.
- この発見は標準の蓄積円盤理論を支持し,蓄積円盤の行動を支配する普遍的なメカニズムを示唆する.
- この結果は,白矮星から超大質量ブラックホールまで,コンパクトな物体の周りの蓄積プロセスが基本的な類似性を共有していることを示唆しています.
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