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Enrichment of the High-Redshift IGM by Galactic Winds

A. Aguirre·J. Schaye·L. Hernquist·D. Weinberg·N. Katz·J. Gardner
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Abstract

This paper discusses a semi-numerical method of investigating the enrichment of the intergalactic medium by galactic winds. We find that most galaxies at z >~ 3 should be driving winds, and that (if these winds are similar to those at low-z) these winds should escape to large distances. Our calculations -- which permit exploration of a large region of model parameter space -- indicate that the wind velocity, the mass of the wind-driving galaxies, the fraction of ambient material entrained, and the available time (between wind launch and the observed redshift) all affect wind propagation significantly; other physical effects can be important but are sub-dominant. We find that under reasonable assumptions, the enrichment by 3 <~ z <~ 6 galaxies could account for the quantity of metals seen in the Ly-alpha forest, though it is presently unclear whether this enrichment is compatible with the intergalactic medium's detailed metal distribution or relative quiescence.

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A. Aguirre, J. Schaye, L. Hernquist, D. Weinberg, N. Katz, J. Gardner. 2001-09-17. Enrichment of the High-Redshift IGM by Galactic Winds. https://arxiv.org/abs/astro-ph/0109278

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