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arXiv · 2404.09028

Relation between the local width and linear halo mass density of cosmic filaments

Weishan Zhu·Tian-Rui Wang·Fupeng Zhang·Yi Zheng·Long-Long Feng
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Abstract

Large-scale cosmic filaments may have played an important role in shaping the properties of galaxies. Meanwhile, cosmic filaments are believed to harbor a substantial portion of the missing baryons at redshift z < 2. To inspect the role of filaments in these issues, many properties of filaments need to be examined, including their lengths, thicknesses, and density profiles. However, measuring some of these properties poses challenges. This study concentrates on estimating filament width/thickness, investigating potential correlations between the local width of filaments and the properties of dark matter halos within filaments. We find that the local width of filaments generally increases with the mass of dark matter halos embedded in filaments per unit length, roughly following a secondorder polynomial, although with notable scatter. We probe and discuss means that may refine our findings. After further verification and improvements, this relation could be applied to filament samples constructed from the observed galaxy distribution, aiding in understanding the roles of cosmic filaments in galaxy evolution and uncovering the missing baryons.

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Weishan Zhu, Tian-Rui Wang, Fupeng Zhang, Yi Zheng, Long-Long Feng. 2024-04-13. Relation between the local width and linear halo mass density of cosmic filaments. https://doi.org/10.3847/1538-4357/ad3e6a

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