近赤外線の銀河外背景光のアニソトロピーの起源について
Michael Zemcov1, Joseph Smidt2, Toshiaki Arai3
1Department of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA 91125, USA. Jet Propulsion Laboratory (JPL), National Aeronautics and Space Administration (NASA), Pasadena, CA 91109, USA.
まとめ
銀河外背景光 (EBL) の変動は,初期の銀河ではなく,剥がれた星からのイントラハロ光 (IHL) を明らかにします. この発見は,IHLが宇宙光子エネルギー予算に大きく貢献す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
- 観測天文学 観測天文学
背景:
- 銀河外背景光 (EBL) のアニソトロピーは,宇宙の光子生成と銀河の調査で見逃された淡い構造についての洞察を提供します.
- 赤外線EBLの変動は議論されており,再イオン化の時代 (EOR) の原始銀河/ブラックホール,または低赤道移転で潮的に剥がれた星からのイントラハロ光 (IHL) の起源が提案されています.
研究 の 目的:
- 特殊な探査ロケット実験を使用して赤外線波長でのEBLアニソトロピーを測定する.
- EBL変動の提案された源,特にEOR銀河/ブラックホールとIHLを区別する.
主な方法:
- 1.1 と 1.6 マイクロメートルでEBLアニソトロピーを測定するための特殊な探査ロケット実験を実施しました.
- 観測された変動を分析し,その振幅と特性を,既知の銀河群と理論モデルの予測と比較した.
主要な成果:
- 観測されたEBLの変動は,既知の銀河集団から予想される振幅を大幅に超えています.
- 測定された変動は,EOR銀河やブラックホールからの放射と矛盾しています.
- データは,観察されたEBLアニソトロピーの主要な源としてIHLを強く支持しています.
- 測定されたEBLの強度は,既知の銀河からの背景と比較可能であり,かなりの宇宙光子エネルギー貢献を示しています.
結論:
- 潮剥離された恒星からのイントラハロ光 (IHL) は,赤外線波長で観測された銀河外背景光 (EBL) のアニソトロピーの主な源です.
- この発見は,初期宇宙の銀河とブラックホールのEBL変動への貢献に異議を唱えている.
- IHLは,宇宙光子エネルギーの総予算の重要な構成要素を表しています.
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