再イオン化時代の間,Δz>0.06という下限値

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Judd D Bowman¹, Alan E E Rogers

¹Arizona State University, School of Earth and Space Exploration, Tempe, Arizona 85287, USA. judd.bowman@asu.edu

|December 15, 2010

まとめ

科学者たちは,初期の宇宙の再イオン化を研究するために,原子水素から21センチメートルの線を観察しました. この研究は,急速な再イオン化の時間スケールを排除し,宇宙の歴史に関する重要な洞察を提供します.

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
初期の宇宙物理学物理学

背景:

原子水素の21センチメートルの線は,初期の宇宙の重要な探査機である.
再イオン化の歴史は,宇宙の進化を理解するために極めて重要です.
21cmの信号を観測することは,弱々しい信号と前景の汚染により困難です.

研究の目的:

21cmの線を使って宇宙の再イオン化の歴史を調査する.
全天スペクトルにおける急速な再イオン化の特徴的なシグネチャーを探す.
再イオン化の時間スケールを制限するために.

主な方法:

21cm線の全空スペクトルを取得しました.
観測周波数帯: 100〜200MHz. 観測周波数帯は100〜200MHz. 観測周波数帯は100〜200MHz. 観測周波数帯は100〜200MHz.
対応する赤偏移の範囲: 6 < z < 13.

主要な成果:

観測された全天空のスペクトルを分析した.
データ分析では,急速な再イオン化の時間軸は除外された.
Δz <0.06の急速再イオン化のタイムスケールは,信頼性95%で排除されました.

結論:

初期の宇宙の再イオン化は急速ではなかった.
この発見は,宇宙再イオン化のモデルに制約を与える.
再イオン化のタイムラインを精密にするためにさらなる観測が必要である.

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