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arXiv · 1111.2059

The Evolution of the Baryon Distribution in the Universe from Cosmological Simulations

Fabrice Durier·Jose Antonio de Freitas Pacheco
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Abstract

The evolution of the baryon distribution in different phases, derived from cosmological simulations, are here reported. These computations indicate that presently most of baryons are in a warm-hot intergalactic (WHIM) medium (about 43%) while at z = 2.5 most of baryons constitute the diffuse medium (about 74%). Stars and the cold gas in galaxies represent only 14% of the baryons at z = 0. For z < 4 about a half of the metals are locked into stars while the fraction present in the WHIM and in the diffuse medium increases with a decreasing redshift. In the redshift range 0 < z < 2.5, the amount of metals in the WHIM increases from 4% to 22% while in the diffuse medium it increases from 0.6% to 4%. This enrichment process is due essentially to a turbulent diffusion mechanism associated to mass motions driven by supernova explosions. At z = 0, simulated blue (late type) galaxies show a correlation of the oxygen abundance present in the cold gas with the luminosity of the considered galaxy that agrees quite well with data derived from HII regions.

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Fabrice Durier, Jose Antonio de Freitas Pacheco. 2011-11-08. The Evolution of the Baryon Distribution in the Universe from Cosmological Simulations. https://doi.org/10.1142/s0218301311040062

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