銀河系の進化. 銀河系の進化. 巨大な星雲に埋め込まれたクワサール四重奏は,遠い宇宙の希少な巨大な構造を明らかにする
Joseph F Hennawi1, J Xavier Prochaska2, Sebastiano Cantalupo3
1Max-Planck-Institut für Astronomie, Heidelberg, Germany. joe@mpia.de.
まとめ
天文学者は,珍しい四重クワザール系を発見し,巨大星雲と原始星群の間のつながりを示唆しています. この発見は,初期の宇宙のガス供給に関する現在の宇宙学的シミュレーションに挑戦しています.
科学分野:
- コスモロジー・コスモロジーとは
- 天体物理学 天体物理学
- 銀河の形成と進化について
背景:
- 銀河は,超大質量ブラックホールの蓄積によって推進される超輝かしいクワザール相を通して進化する.
- クエーザーの相は短いため,クエーザーは稀であり,通常は宇宙で広く分離されています.
研究 の 目的:
- 大規模な構造の中でクエサールの関連性を調査する.
- 巨大な銀河団の形成におけるライマン・アルファ星雲の役割を調査する.
主な方法:
- レッドシフト z ≈ 2 でライマンアルファ放射の調査を行った.
- 巨大な星雲の中の4つのクエザーの物理的な関連を特定しました.
- 周囲の銀河の過密度を分析し,システムの性質を評価した.
主要な成果:
- 巨大な星雲の中に埋め込まれたユニークな四重クワザール系を発見した.
- このシステムは,銀河が著しく過剰に密集している場所にあり,おそらくプロトクラスターの祖先である.
- そのような四重クワザーの偶然の発生の確率は極めて低い (∼10(-7)).
結論:
- ライマン・アルファ星雲は,希少なプロトクラスターの場所と物理的に結びついています.
- 初期の宇宙の巨大な構造は,冷たい,密度の高いガス (∼10~11太陽質量) のかなりの貯蔵庫を有しています.
- このガス供給は,現在の宇宙学的シミュレーションからの予測と矛盾しています.
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