接近红外背景的异构形态来自星系的分散的内光
Asantha Cooray1, Joseph Smidt, Francesco De Bernardis
1Department of Physics and Astronomy, University of California, Irvine, California 92697, USA. acooray@uci.edu
Nature
|October 27, 2012
概括
宇宙近红外背景异质可能起源于早期或矮星系. 新的测量显示了更大的集群振幅,这表明星系中的内星是红移1-4的关键贡献者.
科学领域:
- 宇宙学的宇宙学是什么?
- 天体物理学 天体物理学
- 银河系的形成 星系的形成
背景情况:
- 在宇宙近红外背景 (CNIRB) 辐射中未解决的异构与早期星系 (再电离时代) 和微弱的矮星系有关.
- 之前的研究缺乏足够的空间尺度分辨率,无法最终确定CNIRB异构的主要来源.
- 区分这些来源对于理解早期宇宙星系人口和进化至关重要.
研究的目的:
- 测量CNIRB的异构性功率光谱在广泛的角度尺度 (次弧分钟到一度) 中.
- 通过将新测量与现有模型进行比较,调查CNIRB异构的占主导地位.
- 如果当前的模型不能与观测结果相匹配,则探索其他解释,例如内光.
主要方法:
- 对宇宙近红外背景辐射的异质性功率光谱的分析.
- 从次分钟到一度的角度尺度的测量.
- 观察到的功率频谱与早期和矮星系模型的预测进行比较.
主要成果:
- 测量到的CNIRB异形星系的集群振幅高于仅基于早期或矮星系的模型所预测的.
- 射击噪声水平与微弱星系的贡献一致,排除了需要新的,未被观察到的源群的需求.
- 需要一个增强集群振幅的物理机制来解释这些观测.
结论:
- 观测到的CNIRB异质性可以通过银河系内的内星来解释,而不是仅由早期或矮星系来解释.
- 0.07%至0.2%的内光分数与对暗物质光 (10^9至10^12太阳质量) 的观测结果一致,红移为1至4.
- 这一发现突显了内光对宇宙红外背景和星系演变的重大贡献.
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