Formation of massive Population III galaxies through photoionization feedback: a possible explanation for CR 7
Formation of massive Population III galaxies through photoionization feedback: a possible explanation for CR 7
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通过光电离反馈形成大量 III 族星系：CR 7 的可能解释
DOI：
10.1093/mnrasl/slw071
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发表时间：
2016
影响因子：
4.8
通讯作者：
G. Bryan
中科院分区：
文献类型：
--
作者：
E. Visbal;Z. Haiman;G. Bryan
我们探讨了通过光电离反馈的大规模高红移人口III（Pop III）星系的形成。我们认为暗物质晕形成的祖先没有经历过星星形成的早期再电离和附近的星系造成的光蒸发的结果。一旦这样的晕达到10 9 M质量，对应于光热星系际介质（IGM）的金斯质量，原始气体能够坍缩到晕中，可能产生大规模的Pop III星暴。我们认为，这种情况可以解释最近在CR7中观察到的强He II 1640 A线发射，这与年轻的Pop III星的10 7 M一致。如果没有光电离反馈的情况下，这样大质量的Pop III恒星是不可能的，因为星星的形成预计会将金属注入到原子冷却阈值以上的晕中（z = 7时为10 8 M）。我们使用合并树来分析估计通过这个通道形成的可观测Pop III星系的丰度，并在z = 6.6（CR7的红移）处发现数密度为10 −7 Mpc −3。这比亮度与CR7相当的Lyα发射体的密度低约10倍。
We explore the formation of massive high-redshift Population III (Pop III) galaxies through photoionization feedback. We consider dark matter halos formed from progenitors that have undergone no star formation as a result of early reionizatio n and photoevaporation caused by a nearby galaxy. Once such a halo reaches� 10 9 M⊙, corresponding to the Jeans mass of the photoheated intergalactic medium (IGM) atz � 7, pristine gas is able to collapse into the halo, potentially producing a massive Pop III starburst. We suggest that this scenario may explain the recent observation of strong He II 1640 A line emission in CR7, which is consistent with � 10 7 M⊙ of young Pop III stars. Such a large mass of Pop III stars is unlikely without the photoionization feedback scenario, because star formation is expected to inject metals into halos above the atomic cooling threshold (� 10 8 M⊙ at z � 7). We use merger trees to analytically estimate the abundance of observable Pop III galaxies formed through this channel, and find a number density of � 10 −7 Mpc −3 at z = 6.6 (the redshift of CR7). This is approximately a factor of ten lower than the density of Lyα emitters as bright as CR7.
Illustris 宇宙中的氢再电离
影响因子：
4.8
作者：
Bauer A
通讯作者：
Bauer A