コロナがブラックホールで収縮する
E Kara1,2,3,4, J F Steiner5, A C Fabian6
1University of Maryland, College Park, MD, USA. ekara@astro.umd.edu.
Nature
|January 11, 2019
まとめ
星の質量を持つブラックホールの 蓄積円盤は 短いX線反響の遅延を示し 縮小するコロナを示しています これは,光スペクトルの変化の主な原動力としてディスクの断片化を示唆する以前のモデルに異議を唱えます.
科学分野:
- * 天体物理学
- * 高エネルギー天体物理学
- * ブラックホールの蓄積物理学
背景:
- * 恒星質量ブラックホールの周りの収縮流の幾何学は毎月変化する.
- * 硬い (熱いコロナ) から柔らかい (薄いディスク) 状態へのスペクトル移行は議論されています.
- * 超大質量ブラックホールのX線反響の遅延は,コンパクトなコロナとほぼブラックホールの円盤を示唆する.
研究 の 目的:
- * 恒星質量ブラックホールの蓄積流の幾何学を研究する.
- * ブラックホールの蓄積状態におけるスペクトルトランジションの原動力を決定する.
- * 円盤の縮小とコロナ縮小の議論を解決する
主な方法:
- *ブラックホールのトランジエント MAXI J1820+070のX線観測
- * コロナと蓄積円盤の間の反響時間遅れの分析
- * 拡大された鉄K排出ラインプロフィールの監視
主要な成果:
- * レバーベレーションの遅れは以前より6~20倍短かった.
- * ラグの時間スケールは数週間にわたって数桁の大きさで減少した.
- * 鉄Kの排出線形は,観測期間中に一定であった.
結論:
- * 発見は,コロナの空間的範囲の減少を示唆しています.
- * これは,蓄積円盤の内縁の変化を強調するモデルと矛盾しています.
- * この研究は,ブラックホールの蓄積力学に関する新しい洞察を提供します.
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