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Mixing of Primordial Gas in Lyman Break Galaxies

Liubin Pan·John Scalo
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Abstract

Motivated by an interpretation of $z \sim 3$ objects by Jimenez and Haiman (2006), we examine processes that control the fraction of primordial ($Z = 0$) gas, and so primordial stars, in high-SFR Lyman break galaxies. A primordial fraction different from 1 or 0 requires microscopic diffusion catalyzed by a velocity field with timescale comparable to the duration of star formation. The only process we found that satisfies this requirement for LBGs without fine-tuning is turbulence-enhanced mixing induced by exponential stretching and compressing of metal-rich ejecta. The time-dependence of the primordial fraction for this model is calculated. We show that conclusions for all the models discussed here are virtually independent of the IMF, including extremely top-heavy IMFs.

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Liubin Pan, John Scalo. 2006-11-13. Mixing of Primordial Gas in Lyman Break Galaxies. https://doi.org/10.1086/510779

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