Constraints on the star formation efficiency of galaxies during the epoch of reionization
Constraints on the star formation efficiency of galaxies during the epoch of reionization
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DOI：
10.1093/mnras/stw980
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发表时间：
2015-12
影响因子：
4.8
通讯作者：
Guochao Sun;S. Furlanetto
中科院分区：
文献类型：
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作者：
Guochao Sun;S. Furlanetto
再电离被认为是发生在红移范围6 - 6匹配的测量星系光度函数在这些红移。我们发现，在晕质量M = 10^（11）-10 ^（12）M时，f的峰值在0.30%，这与它在较低红移时的行为定性一致。然后，我们调查的宇宙星星形成的历史和相应的模型的再电离范围内的小晕质量的外推。我们使用各种观测来进一步限制星系种群的特征，包括紫外光子的逃逸分数。我们的方法提供了一个经验校准，物理激励模型的恒星形成星系源的再电离时代的属性。在低质量晕中形成星星的效率最高的情况下，平均逃逸分数为0.1可以重现普朗克报告的光学深度，而在这些晕中形成低效的星星需要大约两倍的紫外光子逃逸，或者逃逸分数向更高的红移增加。我们的模型还预测了詹姆斯韦伯太空望远镜未来的观测如何提高我们对这些星系群的理解。
Reionization is thought to have occurred in the redshift range of 6 6 that matches the measured galaxy luminosity functions at these redshifts. We find that f⋆ peaks at ∼30 per cent at halo masses M ∼ 10^(11)–10^(12) M⊙, in qualitative agreement with its behaviour at lower redshifts. We then investigate the cosmic star formation histories and the corresponding models of reionization for a range of extrapolations to small halo masses. We use a variety of observations to further constrain the characteristics of the galaxy populations, including the escape fraction of UV photons. Our approach provides an empirically calibrated, physically motivated model for the properties of star-forming galaxies sourcing the epoch of reionization. In the case where star formation in low-mass haloes is maximally efficient, an average escape fraction ∼0.1 can reproduce the optical depth reported by Planck, whereas inefficient star formation in these haloes requires either about twice as many UV photons to escape, or an escape fraction that increases towards higher redshifts. Our models also predict how future observations with James Webb Space Telescope can improve our understanding of these galaxy populations.