Modelled vs observed abundances of EMP stars

The supernova yields are prepared with nucleosynthesis calculations of metal-free stars with various initial masses (M=13, 15, 25, 40 and 100M_{sun}_) and explosion energies (E_51_=E/10^51^[erg]=0.5-60), to include low-energy, normal-energy, and high-energy explosions.

We adopt the mixing-fallback model, to take into account possible asymmetry in the supernova explosions, and the yields that best fit the observed abundance patterns of the EMP stars are searched by varying the model parameters. We find that the abundance patterns of the EMP stars are predominantly best- fitted by the supernova yields with initial masses M<40M_{sun}_, and that more than than half of the stars are best-fitted by the M=25M_{sun}_ hypernova (E_51_=10) models.