论文标题
失踪重子的鹰视图
An EAGLE view of the missing baryons
论文作者
论文摘要
语境。在当地宇宙中，预测的重量很大一部分仍未发现。我们采用了一个共同的假设，即缺少的重子的一小部分对应于温暖热热层间培养基（WHIM）的热（log t（k）= 5.5-7）相。我们将缺失的Baryons搜索基于该场景，从而通过积聚冲击和银河流出加热了，并集中在宇宙网的细丝上。 目标。我们的目的是改善对未检测到的Hot Hot的观察性搜索。 方法。我们通过将双重形式主义应用于星系分布来检测鹰模拟中的丝状结构。此外，我们还使用Eagle暗物质组件的大规模环境的MMF/Nexus+分类。然后，我们研究了提取的丝中热重子的空间 - 热分布。 结果。虽然细丝仅占完整模拟量的5％，但细丝的漫射热层间培养基为23％$ - $ 25％的巴里昂预算的25％，或79％$ - $ 87％的热潮$ 87％。通过选择具有高星系光度密度的双丝丝，获得了最佳的灯丝样品，其遗漏的重子质量分数为82％。对于这些细丝，我们得出了径向气体密度和温度曲线的分析公式，这与中央$ r $ $ $ $ $ 1 MPC内的最新Planck SZ和CMB镜头观测一致。 结论。 Eagle的结果表明，丢失的Baryons强烈集中在细丝轴上。由于此处使用的细丝查找方法适用于星系调查，因此可以通过将观察性努力集中在细丝的中央1 MPC区域来定位。此外，关注高星系光度密度区域将优化观察信号。
Context. A significant fraction of the predicted baryons remains undetected in the local universe. We adopted the common assumption that a large fraction of the missing baryons corresponds to the hot (log T(K) = 5.5-7) phase of the Warm Hot Intergalactic Medium (WHIM). We base our missing baryons search on the scenario whereby the WHIM has been heated up via accretion shocks and galactic outflows, and is concentrated towards the filaments of the Cosmic Web. Aims. Our aim is to improve the observational search of the poorly detected hot WHIM. Methods. We detect the filamentary structure within the EAGLE simulation by applying the Bisous formalism to the galaxy distribution. In addition, we use the MMF/NEXUS+ classification of the large scale environment of the dark matter component in EAGLE. We then study the spatio-thermal distribution of the hot baryons within the extracted filaments. Results. While the filaments occupy only 5% of the full simulation volume, the diffuse hot intergalactic medium in filaments amounts to 23% $-$ 25% of the total baryon budget, or 79% $-$ 87% of all the hot WHIM. The most optimal filament sample, with a missing baryon mass fraction of 82%, is obtained by selecting Bisous filaments with a high galaxy luminosity density. For these filaments we derived analytic formulae for the radial gas density and temperature profiles, consistent with recent Planck SZ and CMB lensing observations within the central $r$~ 1 Mpc. Conclusions. Results from EAGLE suggest that the missing baryons are strongly concentrated towards the filament axes. Since the filament finding methods used here are applicable to galaxy surveys, a large fraction of the missing baryons can be localised by focusing the observational efforts on the central 1 Mpc regions of the filaments. Moreover, focusing on high galaxy luminosity density regions will optimise the observational signal.
