ビッグバンから20億年後の原始的なガスの検出
Michele Fumagalli1, John M O'Meara, J Xavier Prochaska
1Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA, USA. mfumagalli@ucolick.org
Science (New York, N.Y.)
|November 15, 2011
まとめ
天文学者は,最小限の重元素を含む2つの古代のガス雲を検出し,初期の宇宙の構成に関する洞察を提供しました. この発見は標準宇宙学モデルを裏付け,重元素の不均一な分布を明らかにした.
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
- 核合成は,核合成である.
背景:
- 標準宇宙論モデルは,ビッグバンで形成されたのは軽い元素のみで,重い元素は後に星で合成されたと仮定している.
- すべての観測された天体物理環境における重元素の存在は,このモデルに異議を唱える.
- 初期の元素の豊富さと分布を理解することは,宇宙論の理論を検証するために極めて重要です.
研究 の 目的:
- 重元素の濃度が非常に低い2つのガス雲の検出を報告する.
- これらの雲の組成を,金属が少ないハロ星のための潜在的な燃料として調査する.
- 原始核合成と標準宇宙モデルに関する予測を検証する.
主な方法:
- 遠く離れた2つのガス雲の観測とスペクトル分析.
- 水素よりも重い元素に焦点を当てて元素の豊富さを測定する.
- 原始核合成の予測を確認するためにデウテリウム検出.
主要な成果:
- 水素より重い元素を識別できない2つのガス雲が検出されました.
- これらのシステムは,初期の宇宙で観測された最も低い重元素の豊富さを表しています.
- デウテリウムは,原始核合成の予測と一致するレベルで検出されました.
結論:
- この発見は,標準宇宙学モデルを直接裏付けるものである.
- 観測された低重元素の豊富さは,これらの雲が初期の星の原始的な燃料である可能性があることを示唆しています.
- 銀河から周囲への重元素の不均質な輸送が暗示されている.
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