Formation of compact stellar clusters by high-redshift galaxy outflows. II. effect of turbulence and metal-line cooling

Abstract

In the primordial universe, low-mass structures with virial temperatures less than 104K 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, 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 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 ≈ 10 -2 Z ⊙. As in our previous simulations, all of these properties suggest that these interactions may have given rise to present-day halo globular clusters. © 2011. The American Astronomical Society. All rights reserved.