重力レンズ付きクワサールの中心の画像
Joshua N Winn1, David Rusin, Christopher S Kochanek
1Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA. jwinn@cfa.harvard.edu
Nature
|February 13, 2004
まとめ
科学者たちは,行方不明の生物を特定しました.
科学分野:
- 天文学と天体物理学について
- コスモロジー・コスモロジーとは
背景:
- 銀河は重力レンズとして機能し,背景の天体の複数の画像を作成することができます.
- 理論は奇数のレンズ画像を予測していますが,ほとんどの観察されたケースは2枚または4枚の画像を示しています.
- 難解な"中央"の画像は,淡く,レンズ状の銀河の核の近くにあると予測されており,遠くの銀河の中心を研究するのに不可欠です.
研究 の 目的:
- 以前に検出されていなかった"中心"の重力画像を確実に識別するために.
- 特定された中央画像を使用して,レンズ銀河の核の特性を詳細に分析します.
主な方法:
- ラジオ観測は,重力レンズ系候補で実施された.
- レンズモデリングは,新たに識別された中央画像を組み込むように実行されました.
主要な成果:
- ラジオ観測により,決定的な中央画像が特定されました.
- レンズ状の銀河の中心にある超大質量ブラックホールの質量は,太陽の質量2×10^8未満に制限された.
- レンズ状の銀河の表面密度は,パーセック2分の2あたり2万太陽質量より大きいと判断されました.
結論:
- 中央画像の安全な識別は,銀河の核を調査するための新しいツールを提供します.
- この結果は,理論的な期待と近隣の銀河の観測と一致し,この発見を裏付けている.
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