遠赤外線背景光の半分以上は,z >or= 1.2の銀河から来ている
Mark J Devlin1, Peter A R Ade, Itziar Aretxaga
1Department of Physics & Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, Pennsylvania 19104, USA. devlin@physics.upenn.edu
Nature
|April 11, 2009
まとめ
サブミリメートルの調査では,遠赤外線背景光 (FIRB) のほとんどは,高赤偏移の明るい銀河から発生していることを明らかにしています. z > 1.2で観測されたこれらの塵の星爆発銀河は,この宇宙放射線の主な貢献者です.
科学分野:
- 銀河外天文学 銀河外天文学
- 宇宙塵の研究 宇宙塵の研究
- 銀河の進化 銀河の進化 銀河の進化
背景:
- サブミリメートルの観測で,高赤道偏移で,明るい,塵の多い星空の銀河が発見されました.
- これらの銀河は,局所宇宙の何百倍もの速度で,遮蔽された恒星形成を示しています.
- 星の光は塵によって吸収され,遠赤外線で再放射され,宇宙の背景に寄与します.
研究 の 目的:
- 集積された遠赤外線背景 (FIRB) を個々の銀河からの貢献に分解する.
- サブミリメートルの波長で銀河外背景放射の源を調査する.
- FIRBを放射する銀河の赤道偏移分布を決定する.
主な方法:
- 250,350,500マイクロメートルで銀河外調査を行った.
- 新しい500マイクロメートルのデータと既存の24マイクロメートルの観測を組み合わせた.
- 分析されたスペクトルエネルギー分布と赤偏移情報.
主要な成果:
- 遠赤外線背景光 (FIRB) のすべては,個々の銀河に属している.
- 赤道偏移 z >or= 1.2 の銀河は,FIRBの70%を占めています.
- z > 1の超光輝銀河は,最も長い波長 (500マイクロメートル) の信号を支配する.
結論:
- FIRBは,主に高赤道移転,塵の多いスターバースト銀河によって生成されます.
- z > 1 の銀河集団は,初期の宇宙のエネルギー予算を理解するために不可欠です.
- 解明された個々の銀河は,観測されたFIRBの全体性を説明します.
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