Reionization of the Milky Way, M31, and their satellites I: reionization history and star formation
Reionization of the Milky Way, M31, and their satellites I: reionization history and star formation
复制标题
银河系、M31 及其卫星的再电离 I：再电离历史和恒星形成
DOI：
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Y. Hoffman
中科院分区：
文献类型：
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作者：
K. Dixon;I. Iliev;S. Gottlober;G. Yepes;A. Knebe;N. Libeskind;Y. Hoffman
对银河系(MW)、M31及其附近被称为本地域群(LG)的观测，可以提供关于再电离来源的线索。我们提出了一套基于约束局部宇宙模拟(LEOES)项目提供的初始条件的辐射传输模拟，该项目旨在重建局部宇宙，包括现实的MW-M31对和附近的处女座。我们的盒子尺寸(91Mpc)足够大，可以容纳LG的相关电离光子源。我们使用了一系列源模型，模拟了暗物质晕辐射反馈的潜在影响，范围在$10^{8}-10^{9}$M${\ODOT}$之间。尽管LG主要是以由内向外的方式进行再电离，但其最后40%的电离显示出一些外部影响。对于LG卫星，我们没有发现任何证据表明它们的再电离红移与目前卫星的质量或与中心星系的距离有关。我们发现，在目前的MW和M31卫星中，只有不到20%的卫星在全球再电离结束之前经历过任何恒星形成。这些卫星中大约有5%可以归类为化石，这意味着大多数恒星的形成都发生在这些早期。在全球再电离结束之前，质量越大的卫星有更多的累积恒星形成，但散射是显著的，特别是在低质量端。目前的质量和距中央星系的距离不能很好地预测卫星星系中是否存在古老的恒星群。
Observations of the Milky Way (MW), M31, and their vicinity, known as the Local Group (LG), can provide clues about the sources of reionization. We present a suite of radiative transfer simulations based on initial conditions provided by the Constrained Local UniversE Simulations (CLUES) project that are designed to recreate the Local Universe, including a realistic MW-M31 pair and a nearby Virgo. Our box size (91 Mpc) is large enough to incorporate the relevant sources of ionizing photons for the LG. We employ a range of source models, mimicking the potential effects of radiative feedback for dark matter haloes between $10^{8}-10^{9}$ M$_{\odot}$. Although the LG mostly reionizes in an inside-out fashion, the final 40 per cent of its ionization shows some outside influence. For the LG satellites, we find no evidence that their redshift of reionization is related to the present-day mass of the satellite or the distance from the central galaxy. We find that less than 20 per cent of present-day satellites for MW and M31 have undergone any star formation prior to the end of global reionization. Approximately five per cent of these satellites could be classified as fossils, meaning the majority of star formation occurred at these early times. The more massive satellites have more cumulative star formation prior to the end of global reionization, but the scatter is significant, especially at the low-mass end. Present-day mass and distance from the central galaxy are poor predictors for the presence of ancient stellar populations in satellite galaxies.
影响因子：
8.7
作者：
Komatsu, E.;Smith, K. M.;Wright, E. L.
通讯作者：
Wright, E. L.