贫瘠而非空无：虚宿（Void）环境对星系和晕族（halo population）的影响

本文探讨了宇宙膨胀（expansion of the universe）如何导致低密度虚宿区域的形成，并分析了这些区域对星系及晕族演化的影响。通过宇宙学模拟（cosmological simulation），研究发现虚宿内的晕质量普遍低于一般区域，且核心密度是影响晕族分布的相关参数（relevant parameter）。

arXiv:2608.26256v1 Announce Type: new Abstract: The combination of gravitational collapse and an accelerating expansion of the Universe drive an increasing fraction of volume toward becoming low-density voids across cosmic time. These regions present a unique environment due to their low density, which leads to them behaving similarly to "pocket universes" with modified cosmological parameters. Since the formation and evolution of galaxies is strongly tied to the environment, we aim to discern how voids alter halos and galaxies compared to the general population in the universe. We use the hydrodynamical cosmological simulation suite Magneticum Pathfinder and introduce a set of void halo mass functions (VHMFs), which trace the halo population as a function of void-centric distance. We find galactic halos in voids to be overall less massive than in the general simulation volume. This discrepancy between void and field halos evolves with time as the voids grow more underdense, while the populations are still very similar at cosmic dawn. Expanding on this, we evaluate whether specific properties of the voids affect the VHMFs. We find the only relevant parameter for the void halo population to be the core density, a measure of the strength of underdensity. To assess the impact of