ライトマン-α放射で明らかにされた宇宙の糸状の糸は,高赤偏移の光るクエーサーの周りを回っている
Sebastiano Cantalupo1, Fabrizio Arrigoni-Battaia2, J Xavier Prochaska3
11] Department of Astronomy and Astrophysics, University of California, 1156 High Street, Santa Cruz, California 95064, USA [2] University of California Observatories, Lick Observatory, 1156 High Street, Santa Cruz, California 95064, USA.
Nature
|January 28, 2014
まとめ
天文学者はライマン・アルファ放出で宇宙の糸糸を観察し,広範囲の銀河間ガスを明らかにしました. この発見は,現在のシミュレーションが,宇宙のウェブにあるガスの量を過小評価している可能性があることを示唆しています.
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
- 銀河の形成 銀河の形成
背景:
- 宇宙学的シミュレーションは,銀河を囲む稀化し,イオン化されたガスの宇宙の網を予測しています.
- 吸収によるこのガスの研究は,一次元の探査機に限られており,3D形態学的分析を妨げています.
- 以前の方法では,宇宙ウェブの3D構造に直接的な制約がありませんでした.
研究 の 目的:
- 放射中の宇宙の糸を直接観察し,特徴づけること.
- 銀河間ガスの3D形態とガスの含有量を調査する.
- 観測データを宇宙学的シミュレーションからの予測と比較する.
主な方法:
- 明るいクワザーを用いて,光で照らされた宇宙ガスの調査を行った.
- クワザールUM 287と関連した宇宙の糸から観測されたライマン・アルファ放射.
- 予想されるサイズを測定し,電磁鉄の冷たいガス質量を推定した.
主要な成果:
- レッドシフト z ≈ 2.3.3 でライマン-アルファ放射の宇宙の糸糸を発見した.
- この光線は約460物理キロパルセックにわたって広がり,暗黒物質のハロウィリアル半径を超えて広がっています.
- 推定冷気質量は,シミュレーションで通常に見られるよりも (10倍以上) 大きくなります.
結論:
- 観測された光線は銀河間ガスを直接追跡し,3D形態学的洞察を提供している.
- 現在の宇宙学的シミュレーションでは,サブキロパーセック級の銀河間ガス塊の集団が欠落している可能性があります.
- この発見は,モデルとコスミック・ウェブのガス含有量に関する観測の間の潜在的な不一致を強調している.
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