Metal enrichment of the intergalactic medium
Metal enrichment of the intergalactic medium
复制标题
星际介质的金属富集
DOI：
10.1111/j.1365-8711.1998.01156.x
复制
发表时间：
1997
影响因子：
4.8
通讯作者：
N. Gnedin
中科院分区：
文献类型：
--
作者：
N. Gnedin
我证明通过高分辨率的宇宙学模拟，其中包括一个两相星际介质的建模，运输重元素从原星系到星系际介质（IGM）的主导机制是合并机制，发现Gnedin和Ostriker。超新星对星际气体的直接喷射在将金属输送到IGM中只起了很小的作用：在现实的宇宙学场景中，IGM中只有一小部分金属是由超新星驱动的风输送的，而IGM中的大多数金属是由合并机制输送的。因此，IGM中的金属丰度分布是高度不均匀的，与类星体金属吸收系统的研究一致，预测的莱曼α吸收体的金属丰度分布作为其柱密度的函数与观测数据非常吻合。
I demonstrate by means of high-resolution cosmological simulations, which include modelling of a two-phase interstellar medium, that the dominant mechanism for transporting heavy elements from protogalaxies into the intergalactic medium (IGM) is the merger mechanism as discovered by Gnedin & Ostriker. Direct ejection of the interstellar gas by supernovae plays only a minor role in transporting metals into the IGM: for a realistic cosmological scenario only a small fraction of all metals in the IGM is delivered by the supernova-driven winds, while most of the metals in the IGM are transported by the merger mechanism. As a result, the metallicity distribution in the IGM is highly inhomogeneous, in agreement with studies of the QSO metal absorption systems, and the predicted metallicity distribution of Lyman alpha absorbers as a function of their column density is in excellent agreement with the observational data.