銀河との出会いの化石記録
David Elbaz1, Catherine J Cesarsky
1Service d'Astrophysique/CEA, CE Saclay, F-91191 Gif-sur-Yvette, France.
Science (New York, N.Y.)
|April 12, 2003
まとめ
宇宙赤外線背景画像 (CIRB) によると,ほとんどの恒星は,0.8.8の赤道移転の周囲の塵の星爆発銀河で形成されている. 銀河の相互作用と構造の形成は,これらのスターバーストを誘発し,宇宙を形作るようです.
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
- 銀河の進化 銀河の進化 銀河の進化
背景:
- 宇宙赤外線背景 (CIRB) は,宇宙時間における恒星や銀河からの宇宙光放射の重要な部分を表しています.
- 以前の観測により,CIRBのかなりの部分が解明され,宇宙の歴史を通じて銀河の集団についての洞察が得られました.
研究 の 目的:
- 宇宙赤外線背景 (CIRB) に主な貢献者を特定する.
- CIRBの形成における銀河の進化と相互作用の役割を理解する.
主な方法:
- 赤外線宇宙観測所 (ISO) カメラからのデータを利用して,CIRB. を解く.
- 解決されたソースのスペクトルおよび空間特性を分析し,CIRBへの貢献を決定します.
主要な成果:
- 赤道偏差 z ≈ 0.8 の明るいスターバースト銀河は,CIRB の支配的な寄与者として特定されています.
- より高い赤偏移 (z ≥2) の源は,より長い赤外線波長でより顕著になります.
- この研究は,現代のほとんどの星の形成を,銀河の相互作用と大規模構造の形成によって引き起こされる塵の星爆発と関連付けています.
結論:
- スターバースト銀河,特に赤道偏移 z ≈ 0.8 の銀河は,CIRB を理解するための鍵です.
- 銀河の合併と宇宙構造の成長は,恒星形成を推進し,CIRBに影響を与える重要なメカニズムです.
- CIRBは,宇宙時代にわたる恒星と銀河の進化の貴重な探査機として機能しています.
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