Dynamics of stellar black holes in young star clusters with different metallicities - I. Implications for X-ray binaries

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We present N-body simulations of intermediate-mass (3000-4000 Msun) young star clusters (SCs) with three different metallicities (Z=0.01, 0.1 and 1 Zsun), including metal-dependent stellar evolution recipes and binary evolution.

• Following recent theoretical models of wind mass loss and core collapse supernovae, we assume that the mass of the stellar remnants depends on the metallicity of the progenitor stars.
• In particular, massive metal-poor stars (Z<=0.3 Zsun) are enabled to form massive stellar black holes (MSBHs, with mass >=25 Msun) through direct collapse.
• We find that three-body encounters, and especially dynamical exchanges, dominate the evolution of the MSBHs formed in our simulations.