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arXiv 1402.2976astro-ph.CO
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关于空穴密度分布的普遍性

On the universality of void density profiles

E. Ricciardelli, V. Quilis, J. Varela

摘要:

在即将到来的暗能量实验中,为了精确的宇宙学而大量利用宇宙空隙,需要对它们的内部结构,特别是它们的密度分布有一个强有力的理解。我们发现,无论是在一个目录中观察到的空隙和空隙从一个大的宇宙学模拟的空隙密度分布是不敏感的空隙半径。然而,观察到的和模拟的空隙显示显着不同的轮廓形状,前者具有更陡峭的轮廓比后者。稀疏性不能是这种差异的主要原因,因为我们证明了即使是非常稀疏的示踪剂样本,也可以以合理的精度恢复轮廓。另一方面,观察到的配置文件显示了显着依赖于用于跟踪物质分布的星系样本。包括低质量星系的样本导致比仅使用大质量星系的样本更浅的轮廓,因为微弱的星系更靠近空洞中心。我们认为,星系是有偏见的示踪剂时,用于探测空洞内的物质分布。

英文摘要:

The massive exploitation of cosmic voids for precision cosmology in the upcoming dark energy experiments, requires a robust understanding of their internal structure, particularly of their density profile. We show that the void density profile is insensitive to the void radius both in a catalogue of observed voids and in voids from a large cosmological simulation. However, the observed and simulated voids display remarkably different profile shapes, with the former having much steeper profiles than the latter. Sparsity can not be the main reason for this discrepancy, as we demonstrate that the profile can be recovered with reasonable accuracy even with very sparse samples of tracers. On the other hand, the observed profile shows a significant dependence on the galaxy sample used to trace the matter distribution. Samples including low-mass galaxies lead to shallower profiles with respect to the samples where only massive galaxies are used, as faint galaxies live closer to the void centre. We argue that galaxies are biased tracers when used to probe the matter distribution within voids.

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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