近いクワザールペアを用いた銀河間媒体の小規模構造の測定
Alberto Rorai1,2, Joseph F Hennawi2,3, Jose Oñorbe2
1Institute of Astronomy, Cambridge, UK. arorai@ast.cam.ac.uk.
Science (New York, N.Y.)
|April 29, 2017
まとめ
科学者はクエーザーの吸収線を用いて 銀河間媒介 (IGM) の圧縮スケールを測定した. 初期の宇宙の仕組みを 理解するのに役立ちます
科学分野:
- 宇宙学
- 天体物理学
- 銀河間メディア物理学
背景:
- 銀河間媒質 (IGM) には 遠くのクエーサーからの光を吸収し ライマン・アルファ・フォレストを形成する 拡散したガスが含まれています
- 宇宙学的シミュレーションは,IGM密度の変動が熱圧によって抑制される特徴的なスケールを予測します.
- 宇宙の熱の歴史と再イオン化を 理解するには この圧縮スケールの理解が 極めて重要です
研究 の 目的:
- IGMの圧縮スムージングスケールを測定する
- 宇宙学的水力学シミュレーションからの予測と観測データを比較する.
- 再イオン化時代における光イオン化加熱のモデルをテストする.
主な方法:
- クワザールペアの吸収相関を分析する
- クエーサーのスペクトルに刻まれたライマン・アルファの森を利用して
- 熱の歴史を組み込む水力学シミュレーションと比較する.
主要な成果:
- 吸収の相関を分析して,圧力の滑らかなスケールを定量化した.
- 測定は水力学シミュレーションと比較した.
- 理論的予測と一致しています
結論:
- 測定された圧力滑らかなスケールは,光イオン化加熱の標準モデルと一致しています.
- この結果は 宇宙の再イオン化における 紫外線背景の役割に関する 現在の理解を裏付けています
- この研究は,初期のIGMの熱状態に関する観察的制約を提供します.
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