Population III Star Formation in a ΛCDM Universe. I. The Effect of Formation Redshift and Environment on Protostellar Accretion Rate

  title={Population III Star Formation in a $\Lambda$CDM Universe. I. The Effect of Formation Redshift and Environment on Protostellar Accretion Rate},
  author={Brian W. O’Shea and Michael L. Norman},
  journal={The Astrophysical Journal},
We perform 12 extremely high resolution adaptive mesh refinement cosmological simulations of Population III star formation in a ΛCDM universe, varying the box size and large-scale structure, to understand systematic effects in the formation of primordial protostellar cores. We find results that are qualitatively similar to those of previous groups. We observe that in the absence of a photodissociating ultraviolet background, the threshold halo mass for formation of a Population III protostar… Expand
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