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arXiv · 1103.4369

Formation of Compact Stellar Clusters by High-Redshift Galaxy Outflows II: Effect of Turbulence and Metal-Line Cooling

William Gray·Evan Scannapieco
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Abstract

In the primordial universe, low mass structures with virial temperatures less than 10$^{4}$ K were unable to cool by atomic line transitions, leading to a strong suppression of star formation. On the other hand, these "minihalos" were highly prone to triggered star formation by interactions from nearby galaxy outflows. In Gray & Scannapieco (2010), we explored the impact of nonequilibrium chemistry on these interactions. Here we turn our attention to the role of metals, carrying out a series of high-resolution three-dimensional adaptive mesh refinement simulations that include both metal cooling and a subgrid turbulent mixing model. Despite the presence of an additional coolant, we again we find that outflow-minihalo interactions produce a distribution of dense, massive stellar clusters. We also find that these clusters are evenly enriched with metals to a final abundance of Z $\approx$ 10$^{-2}$ Z$_{\odot}$. As in our previous simulations, all of these properties suggest that these interactions may have given rise to present-day halo globular clusters.

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William Gray, Evan Scannapieco. 2011-04-12. Formation of Compact Stellar Clusters by High-Redshift Galaxy Outflows II: Effect of Turbulence and Metal-Line Cooling. https://doi.org/10.1088/0004-637x%2F733%2F2%2F88

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