クワサールBR1202 - 0725における分子ガスの検出 赤道偏移z = 4.69で赤道偏移z = 4.69で
K Ohta1, T Yamada, K Nakanishi
1Department of Astronomy, Kyoto University, Japan.
Nature
|August 1, 1996
まとめ
研究者らは,赤道偏移z=4.69.5で遠いクエーサーBR1202-0725からの一酸化炭素 (CO) 放射を検出した. この発見は,大量の分子水素を持つ巨大な銀河を明らかにし,重要な初期の恒星形成を示しています.
科学分野:
- 天文学と天体物理学について
- 宇宙ガスと銀河の進化について
背景:
- 初期の宇宙で,恒星形成に不可欠な分子ガスを検出することは困難です.
- 以前の,高い赤偏移 (z ≈ 2.5) で分子ガスの検出は,重力レンズ化された物体に限られていた.
研究 の 目的:
- 高赤偏移の無線静かなクワザールからの一酸化炭素 (CO) 放射の検出を報告する.
- 初期の宇宙における分子ガスの存在と質量を調査する.
主な方法:
- 一酸化炭素 (CO) 排出ラインの観測.
- クワサールBR1202-0725.25の赤道移転の決定
主要な成果:
- ラジオ静かなクワザールBR1202-0725からのCO放射の検出 赤道偏移 z = 4.69で.
- クワザールに関連した分子水素の約10^11太陽質量の推定.
- 分子ガスの質量は,現代の輝く銀河の恒星質量に匹敵する.
結論:
- BR1202-0725は,初期の宇宙の巨大な銀河を表しています.
- ガスの中心部に集中しており,恒星形成の大きな爆発が起こっていることを示唆しています.
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