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arXiv 1708.08451astro-ph.CO
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暗物质晕的空间成团:次级偏置、近邻偏置和大质量近邻对晕性质的影响

Spatial Clustering of Dark Matter Halos: Secondary Bias, Neighbor Bias, and the Influence of Massive Neighbors on Halo Properties

Andrés N. Salcedo, Ariyeh H. Maller, Andreas A. Berlind, Manodeep Sinha, Cameron K. McBride, Peter S. Behroozi, Risa H. Wechsler, David H. Weinberg

摘要:

我们探讨的现象通常被称为晕组装偏见,即暗物质晕相同的质量被发现或多或少集群时,第二晕属性被认为是,晕在质量范围$3.7 \times 10^{11} \; h^{-1} \mathrm{M_{\odot}} - 5.0 \times 10^{13} \; h^{-1} \mathrm{M_{\odot}}$。使用大型套件的暗物质模拟(LasDamas),我们认为九个常用的晕属性,并发现存在聚类偏差,如果晕是由质量或任何其他晕属性分仓。这种二次偏置意味着,没有一个单一的晕属性涵盖所有的空间聚类信息的晕人口。一些晕圈性质的平均值取决于它们与更大质量的邻居的距离。因此,通过具有这些属性之一的高值而选择的晕样本继承了邻居偏差,使得它们更有可能接近质量大得多的邻居。这种邻近偏差主要是由于在按质量分组并按浓度或年龄划分的晕中看到的次级偏差。然而,即使当相邻偏差被去除时,由其他质量类似的属性分箱的晕仍然显示二次偏差。由自旋选择的晕的二次偏置行为不同于其他晕属性,表明自旋偏置的起源不同于其他二次偏置。

英文摘要:

We explore the phenomenon commonly known as halo assembly bias, whereby dark matter halos of the same mass are found to be more or less clustered when a second halo property is considered, for halos in the mass range $3.7 \times 10^{11} \; h^{-1} \mathrm{M_{\odot}} - 5.0 \times 10^{13} \; h^{-1} \mathrm{M_{\odot}}$. Using the Large Suite of Dark Matter Simulations (LasDamas) we consider nine commonly used halo properties and find that a clustering bias exists if halos are binned by mass or by any other halo property. This secondary bias implies that no single halo property encompasses all the spatial clustering information of the halo population. The mean values of some halo properties depend on their halo's distance to a more massive neighbor. Halo samples selected by having high values of one of these properties therefore inherit a neighbor bias such that they are much more likely to be close to a much more massive neighbor. This neighbor bias largely accounts for the secondary bias seen in halos binned by mass and split by concentration or age. However, halos binned by other mass-like properties still show a secondary bias even when the neighbor bias is removed. The secondary bias of halos selected by their spin behaves differently than that for other halo properties, suggesting that the origin of the spin bias is different than of other secondary biases.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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