The Epoch of Reionization
The Epoch of Reionization
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DOI：
10.1007/978-3-642-32362-1_2
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发表时间：
2012-06
影响因子：
1.8
通讯作者：
S. Zaroubi
中科院分区：
文献类型：
--
作者：
S. Zaroubi
随着第一代星系的形成，宇宙的黑暗时代结束了。这些物体开始发射紫外线辐射，在它们周围形成电离区域。在形成足够数量的电离源后，宇宙中气体的电离部分迅速增加，直到氢完全电离。宇宙气体从中性变为电离的这段时期被称为宇宙再电离时期。再电离时代与宇宙学中的许多基本问题有关，例如第一个星系的性质、（微型）类星体的物理学、贫金属恒星的形成以及天体物理学中的许多其他重要研究课题。因此，发现它将对早期宇宙结构形成的研究产生深远的影响。本章回顾了这一时代发生的当前观测证据、其关键理论方面和主要特征，以及最终有望揭开这一时代的各种观测探索。特别强调红移 21 厘米探测器、目前正在建造或设计的各种实验，以及我们可以从中学到有关再电离时代的知识。
The Universe’sdark agesend with the formation of the first generation of galaxies. These objects start emitting ultraviolet radiation that carves out ionized regions around them. After a sufficient number of ionizing sources have formed, the ionized fraction of the gas in the Universe rapidly increases until hydrogen becomes fully ionized. This period, during which the cosmic gas went from neutral to ionized, is known as the Universe’s Epoch of Reionization. The Epoch of Reionization is related to many fundamental questions in cosmology, such as properties of the first galaxies, physics of (mini-)quasars, formation of very metal-poor stars and a slew of other important research topics in astrophysics. Hence uncovering it will have far reaching implications on the study of structure formation in the early Universe. This chapter reviews the current observational evidence for the occurrence of this epoch, its key theoretical aspects and main characteristics, and finally the various observational probes that promise to uncover it. A special emphasis is put on the redshifted 21 cm probe, the various experiments that are currently being either built or designed, and what we can learn from them about the Epoch of Reionization.