赤道偏移 z = 6.42 のクエーザーの宿主銀河の分子ガス
Fabian Walter1, Frank Bertoldi, Chris Carilli
1National Radio Astronomy Observatory, PO Box 0, Socorro, New Mexico 87801, USA. fwalter@nrao.edu
Nature
|July 25, 2003
まとめ
この研究では,赤道偏移z = 6.42.2のクワサール宿主銀河で,分子水素のトレーサーである一酸化炭素 (CO) 放射が検出されました. この発見は,初期の宇宙に大量に存在する分子ガスを明らかにし,銀河の急速な進化に決定的な役割を果たしています.
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
- 銀河の進化 銀河の進化 銀河の進化
背景:
- 分子水素 (H2) は,恒星形成と銀河の進化に不可欠です.
- 高赤偏移で分子水素を観測することは,通常,一酸化炭素 (CO) 排出によって追跡されるため,困難です.
- クワザール宿主銀河における以前のCO検出は,赤偏移 z > 2 に限定されていました.
研究 の 目的:
- クワザール宿主銀河の炭素一酸化物 (CO) 放出を記録的に高い赤道移転で検出する.
- 初期の宇宙における分子ガスの存在と豊富さを調査する.
- 銀河の急速な形成と進化の条件を理解する.
主な方法:
- 放射天文学の観測を用いて,CO放射線を検出した.
- クワザールSDSS J114816.64 + 525150.3をターゲットに,赤偏移z = 6.42.3で攻撃した.
- 分析されたスペクトルデータを用いて,分子ガスの存在を確認し,その量を測定した.
主要な成果:
- クワサール SDSS J114816.64 + 525150.3 から z = 6.42.3 で CO 放射が検出されたことを報告しました.
- 分子水素 (H2) 質量を約2×10^10太陽質量で定量化しました.
- この検出は,宇宙の再イオン化の終わりに近づいて,宇宙が現在の年齢の1 / 16 分の1しかなかったときに発生しました.
結論:
- 最も若い銀河の重元素で濃縮された分子ガスの急速な形成を示しています.
- 高赤偏移で銀河の進化モデルの基本的な制約を提供する.
- ビッグバン直後の初期の銀河形成における分子ガスの重要な役割を強調しています.
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