论文标题
建模电离时代的平层低电离金属吸收线系统
Modelling intergalactic low ionisation metal absorption line systems near the epoch of reionization
论文作者
论文摘要
我们解释了红移z $ \ gtrsim $ 5在压力夹层云方面的观察结果。我们发现云由质量$ 11 <\ log m_h/h^{ - 1} m_ \ odot <12 $限制的云层限制，$ 11 <\ log log m_h/h^{ - 1} <12 $提供了对低电离金属吸收器之间柱密度比率的很好描述。然而，其中一些比率需要将辐照板的常规辐射转移模型扩展到球形（或圆柱形）云中，以使视线通过云层的岩心外。在某些系统中，还指出了将硅耗尽到粉尘晶粒上的中等耗竭。推断出的化学丰度范围跨越了太阳能和大型明星之间的恒星种群，如Starburst星系中所产生的那样。与数据相匹配的典型HI柱密度对应于阻尼的Lyman-$α$吸收器（DLAS）或Sub-DLA，尺寸为40 PC至3 kpc，气体$ 3.5 <\ log M_C/M_ \ odot <8 $和Mellicaties $ 0.001-0.01-0.01z_ \ odot $。这样的系统继续对银河规模的数值模拟构成挑战。
We interpret observations of intergalactic low ionisation metal absorption systems at redshifts z $\gtrsim$5 in terms of pressure-confined clouds. We find clouds confined by the expected pressure of galactic haloes with masses $11<\log M_h/h^{-1}M_\odot<12$ provide a good description of the column density ratios between low ionisation metal absorbers. Some of the ratios, however, require extending conventional radiative transfer models of irradiated slabs to spherical (or cylindrical) clouds to allow for lines of sight passing outside the cores of the clouds. Moderate depletion of silicon onto dust grains is also indicated in some systems. The chemical abundances inferred span the range between solar and massive-star dominated stellar populations as may arise in starburst galaxies. The typical HI column densities matching the data correspond to Damped Lyman-$α$ Absorbers (DLAs) or sub-DLAs, with sizes of 40 pc to 3 kpc, gas masses $3.5<\log M_c/M_\odot<8$ and metallicites $0.001-0.01Z_\odot$. Such systems continue to pose a challenge for galaxy-scale numerical simulations to reproduce.
