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arXiv · 1902.09522

The large-scale environment from cosmological simulations II: The redshift evolution and distributions of baryons

Weiguang Cui·Alexander Knebe·Noam I. Libeskind·Susana Planelles·Xiaohu Yang·Wei Cui·Romeel Dave·Xi Kang·Robert Mostoghiu·Lister Staveley-Smith·Huiyuan Wang·Peng Wang·Gustavo Yepes
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Abstract

Following Cui et al. 2018 (hereafter Paper I) on the classification of large-scale environments (LSE) at z = 0, we push our analysis to higher redshifts and study the evolution of LSE and the baryon distributions in them. Our aim is to investigate how baryons affect the LSE as a function of redshift. In agreement with Paper I, the baryon models have negligible effect on the LSE over all investigated redshifts. We further validate the conclusion obtained in Paper I that the gas web is an unbiased tracer of total matter -- even better at high redshifts. By separating the gas mainly by temperature, we find that about 40 per cent of gas is in the so-called warm-hot intergalactic medium (WHIM). This fraction of gas mass in the WHIM decreases with redshift, especially from z = 1 (29 per cent) to z = 2.1 (10 per cent). By separating the whole WHIM gas mass into the four large-scale environments (i.e. voids, sheets, filaments, and knots), we find that about half of the WHIM gas is located in filaments. Although the total gas mass in WHIM decreases with redshift, the WHIM mass fractions in the different LSE seem unchanged.

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Weiguang Cui, Alexander Knebe, Noam I. Libeskind, Susana Planelles, Xiaohu Yang, Wei Cui, Romeel Dave, Xi Kang, Robert Mostoghiu, Lister Staveley-Smith, Huiyuan Wang, Peng Wang, Gustavo Yepes. 2019-03-12. The large-scale environment from cosmological simulations II: The redshift evolution and distributions of baryons. https://doi.org/10.1093/mnras%2Fstz565

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