赤道偏移 z の約 0.8 で,水素21cm の放出の強度マップ
Tzu-Ching Chang1, Ue-Li Pen, Kevin Bandura
1IAA, Academia Sinica, PO Box 23-141, Taipei 10617, Taiwan. tchang@cita.utoronto.ca
Nature
|July 24, 2010
まとめ
天文学者たちは,宇宙の網の中の中性水素から21cmの輝きを集約して,赤偏移を1.12まで検出しました. この画期的な発見は,21cmの強度マッピングを使用して,ダークエネルギーの新しい研究を可能にします.
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
- ラジオ天文学 ラジオ天文学
背景:
- 中性水素探査機からの21cmの放射は,宇宙の暗黒エネルギーである.
- 光学宇宙学は,大気中の赤外線不透明性による赤外線偏移 z ~ 1 で課題に直面しています.
- これまでの21cmの放射検出は,z = 0.24.24に限られていた.
研究 の 目的:
- 赤い偏移 z = 0.53 から 1.12 までの 3 次元の 21 cm の強度フィールドを開発する.
- ダークエネルギー研究のための21cmの強度マッピングの可能性を調査する.
- 高赤偏移で個別の銀河の検出の限界を克服するために.
主な方法:
- 約1万の銀河からの中性水素 (H i) 放射を併算する.
- 光学銀河DEEP2の赤道偏移調査から得られたデータを利用したものです.
- 宇宙の網の中の解明されていない銀河からの集積放射を測定する.
主要な成果:
- z = 0.53 から 1.12 までの3次元21cmの強度フィールドが成功裏に生成されました.
- 中性水素からの合計21cmの輝きは,約4シグマの有意度で検出されました.
- 宇宙学的研究のための21cmの強度マッピングの実現可能性が実証されました.
結論:
- 合計21cmの放射は,より高い赤偏移で暗黒エネルギーの実行可能な探査機です.
- この技術は,特定の赤偏移範囲における光学宇宙学の限界を克服します.
- 宇宙のウェブをマッピングし,宇宙加速を理解するための新しい道を開く.
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