候補赤道移転 z ≈ 10 銀河と,その集団の急速な変化が,500 Myrの年齢で起こる
R J Bouwens1, G D Illingworth, I Labbe
1Department of Astronomy, University of California Santa Cruz, Santa Cruz, California 95064, USA. bouwens@ucolick.org
Nature
|January 29, 2011
まとめ
天文学者は,ハッブル超深場データを用いて初期の銀河を探した. 彼らは,赤道偏移 ~10 で可能な銀河を発見し,初期の宇宙における銀河の急速な成長を示しました.
科学分野:
- 宇宙進化の宇宙進化について
- 銀河の形成 銀河の形成
- 初期の宇宙 天体物理学
背景:
- 赤いシフト3〜6で6000以上の銀河が特定されており,ビッグバンから9億〜2億年後に存在しています.
- ハッブル超深層フィールド (HUDF09) は,赤偏差 ~8の銀河の検出を提供しており,これは発見された最も初期の物体の一つです.
- 以前の観測から,重要な恒星形成は9-10よりも大きな赤道移転で起こったことが示唆されています.
研究 の 目的:
- ビッグバンから約5億年後の赤道~10の銀河の超深層探査を行う.
- 再イオン化時代に恒星形成率の密度を調査するために.
- レッドシフト ~10 と ~8.8 の間の銀河の急速な形成を理解するために.
主な方法:
- 詳細な分析のために,2年間のHUDF09データセットを完全に利用した.
- 赤道偏移 ~10.0で銀河候補の超深層探査を行っています.
- 星形成率の密度を分析する. 源検知と不検知に基づいて.
主要な成果:
- 赤道偏移 ~10 の1つの潜在的な銀河候補が特定されました.
- 赤移り ~10 時の恒星形成率の密度は,赤移り ~8.8 時の密度の約 10% です.
- 銀河の明るさ密度と体積密度の両方の有意な増加は,赤道移り ~10 から ~8.8 から観察されました.
結論:
- 銀河の蓄積は,赤道移転 ~10 と ~8.8 の間で驚くほど迅速でした.
- 赤道移転前1億~2億年の時期は,最も初期の銀河の組立にとって決定的でした.
- この発見は,再イオン化の時代に銀河の形成に関する重要な洞察を提供します.
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