论文标题
探测与MGII森林的电源和早期宇宙富集
Probing Reionization and Early Cosmic Enrichment with the MgII Forest
论文作者
论文摘要
因为相同的巨大恒星恢复了与金属污染宇宙的超新星不可避免地爆炸的巨大恒星，所以宇宙电离和富集的历史紧密地交织在一起。尽管过度敏感的Ly-Alpha过渡在中性IGM中完全饱和，但强大的低离子金属线（如MGII 2796,2804 Doublet）将产生可检测到的“金属线森林”，如果在re元化过程中产生的金属（z〜10^{-3} Z_SOL）enpereate gentral gentral gentral entral entral entral中性igm igm。我们首次通过将大型流体动力学模拟与半数字回离拓扑结合在一起，这是第一次模拟MGII森林，假设一个简单的富集模型，即IgM均匀地充满了金属。与鉴定离散吸收器的传统方法相反，我们将吸收视为连续的随机场并测量其两点相关函数，从精确宇宙学中利用技术。我们表明，10个JWST光谱的现实模拟数据集可以同时确定Mg的丰度[mg/h]，其1 sigma精度为0.02 DEX，并测量具有<x_hi> = 0.74> = 0.74和[mg/h] = 0.74和[mg/h] = -3.7的宇宙的全局中性分数<x_hi>至5％。或者，如果IgM是原始的，则MGII森林的无效检测将对[mg/h] <-4.4的IgM金属性在95％的信誉中设定为<x_hi>> 0.5的IgM金属性。星系环境环境中金属的浓度可能会显着污染IGM信号，但我们证明了如何易于识别和掩盖这些离散的吸收器，从而可以忽略其对相关功能的影响。因此，MGII森林具有精确限制宇宙的电离和丰富历史的巨大潜力。
Because the same massive stars that reionized the intergalactic medium (IGM) inevitably exploded as supernovae that polluted the Universe with metals, the history of cosmic reionization and enrichment are intimately intertwined. While the overly sensitive Ly-alpha transition completely saturates in a neutral IGM, strong low-ionization metal lines like the MgII 2796,2804 doublet will give rise to a detectable `metal-line forest' if the metals produced during reionization (Z ~ 10^{-3}Z_sol) permeate the neutral IGM. We simulate the MgII forest for the first time by combining a large hydrodynamical simulation with a semi-numerical reionization topology, assuming a simple enrichment model where the IGM is uniformly suffused with metals. In contrast to the traditional approach of identifying discrete absorbers, we treat the absorption as a continuous random field and measure its two-point correlation function, leveraging techniques from precision cosmology. We show that a realistic mock dataset of 10 JWST spectra can simultaneously determine the Mg abundance, [Mg/H], with a 1sigma precision of 0.02 dex and measure the global neutral fraction <x_HI> to 5% for a Universe with <x_HI> = 0.74 and [Mg/H] = -3.7. Alternatively, if the IGM is pristine, a null-detection of the MgII forest would set a stringent upper limit on the IGM metallicity of [Mg/H] < -4.4 at 95% credibility, assuming <x_HI> > 0.5 from another probe. Concentrations of metals in the circumgalactic environs of galaxies can significantly contaminate the IGM signal, but we demonstrate how these discrete absorbers can be easily identified and masked such that their impact on the correlation function is negligible. The MgII forest thus has tremendous potential to precisely constrain the reionization and enrichment history of the Universe.
