Three Modes of Metal-Enriched Star Formation in the Early Universe

Understand

Simulations of the formation of Population III (Pop III) stars suggest that they were much more massive than the Pop II and Pop I stars observed today.

• This is due to the collapse dynamics of metal-free gas, which is regulated by the radiative cooling of molecular hydrogen.
• We study how the collapse of gas clouds is altered by the addition of metals to the star-forming environment by performing a series of simulations of pre-enriched star formation at various metallicities.
• For metallicities below the critical metallicity, Z_cr, collapse proceeds similarly to the metal-free case, and only massive objects form.