Statistical properties of mass, star formation, chemical content and rotational patterns in early z > 9 structures

Understand

We study the baryonic, chemical and dynamical properties of a significantly large sample of early proto-galaxies in the first 500 Myr of the Universe (redshift z>9), obtained from high-resolution numerical, N-body, hydrodynamical, chemistry simulations including atomic and molecular networks, gas cooling, star formation, stellar evolution and metal spreading for population III and population II-I regimes according to proper stellar yields and lifetimes.

• We find that first star formation events take place in halos with dark-matter mass M_{DM} > 2\times 10^6 M_{sun}.
• Early star forming objects have: molecular fractions from x_{mol} < 10^{-4} in quiescent structures up to x_{mol} > 0.1 in active regions; star formation rates SFR ~10^{-8}-10^{-3}M_{sun}/yr; and metallicities in the range ~10^{-8}-10^{-2}Z_{sun}.
• Roughly ~10% of high-z haloes host population II-I star formation and dominate the cosmic SFR density.