The enrichment history of cosmic metals
The enrichment history of cosmic metals
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宇宙金属的富集历史
DOI：
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发表时间：
2010
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影响因子：
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通讯作者：
A. Aguirre
中科院分区：
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作者：
R. Wiersma;J. Schaye;C. D. Vecchia;C. Booth;T. Theuns;A. Aguirre
我们使用一套宇宙学、流体动力学模拟来研究宇宙的化学富集历史。具体地说，我们追溯了金属的起源，以调查各种气相何时富集以及由什么晕质量富集。我们发现，金属的年龄随着它们最终进入的气体的密度而大大降低。在红移0(2)的漫射星系间介质（IGM）中，至少有一半的金属是从红移2(3)以上的星系中喷射出来的。最后含有金属的光晕的质量随着气体密度的增加而迅速增加。星系间金属中超过一半的质量是由总质量小于10 11 M⊙和恒星质量小于10 9 M⊙的光晕喷射出来的。在IGM较热的部分，导致富集的光晕质量范围更广。通过结合富集历史的“何时”和“通过什么”两个方面，我们发现存在于低密度气体中的金属通常更早地被低质量晕喷射出来。
We use a suite of cosmological, hydrodynamical simulations to investigate the chemical enrichment history of the Universe. Specifically, we trace the origin of the metals back in time to investigate when various gas phases were enriched and by what halo masses. We find that the age of the metals decreases strongly with the density of the gas in which they end up. At least half of the metals that reside in the diffuse intergalactic medium (IGM) at redshift zero (two) were ejected from galaxies above redshift two (three). The mass of the haloes that last contained the metals increases rapidly with the gas density. More than half of the mass in intergalactic metals was ejected by haloes with total masses less than 10 11 M⊙ and stellar masses less than 10 9 M⊙. The range of halo masses that contributes to the enrichment is wider for the hotter part of the IGM. By combining the ‘when’ and ‘by what’ aspects of the enrichment history, we show that metals residing in lower density gas were typically ejected earlier and by lower mass haloes.