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Simulating Imaging of Large Scale Radio Arrays on the Lunar Surface
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広い線で活動する銀河核は,狭い線で活動する銀河核よりも速く回転する
Wolfram Kollatschny1, Matthias Zetzl
1Institut für Astrophysik, Universität Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen, Germany. wkollat@astro.physik.uni-goettingen.de
Nature
|February 19, 2011
まとめ
活発な銀河核 (AGN) の超大質量ブラックホールは,放射線の幅と形との新しい関係を示しています. この発見は,黒い穴の質量推定を精錬する,支配的なケプラーの回転と乱流を明らかにします.
科学分野:
- 天体物理学 天体物理学
- 銀河の進化 銀河の進化 銀河の進化
- ブラックホール物理学 ブラックホール物理学
背景:
- 活発な銀河核 (AGN) は超大質量ブラックホール (106〜109M) を宿している.
- AGNを取り巻くブロードライン領域 (BLR) は極めて重要だが,その構造と動態は依然として十分に理解されていない.
- 以前の研究では,BLRの支配的な運動 (入流,出流,回転,乱流) と幾何学 (ディスク,球体) についての明確な洞察が欠けている.
研究 の 目的:
- 活発な銀河核における広線領域の構造と動態を調査する.
- BLRの観測されたスペクトル特性を支配する基本的な関係を確立する.
- 中央の超大質量ブラックホールの質量測定を精密にするために.
主な方法:
- 排出ライン幅の分析,特に半最大 (FWHM) の全幅の分析.
- 排出ラインの形状を調べ,FWHM/σ (ライン) の比率で定量化.
- 幅広い線領域の推測された物理条件と幾何学とのスペクトル性質の相関.
主要な成果:
- AGNスペクトルでFWHMとFWHM/σ(ライン) の間の根本的な関係が発見されました.
- 渦巻と組み合わせたケプラーの回転は,BLRs内の支配的な運動として識別されます.
- BLRの幾何学は回転速度と相関する:速い回転機は平らで,遅い回転機は球状である.
- 銀河の中心に向かって幾何学的な厚さが増加する傾向が観察されました.
結論:
- 確立された関係は,BLRのダイナミクスと構造に関する新しい洞察を提供します.
- これらの発見を使用して得られたブラックホールの質量は,以前の推定値より2〜10倍小さい.
- この研究は,AGNにおける中央ブラックホールの質量を決定するためのより正確な方法を提供します.
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