The H II Region of the First Star

  title={The H II Region of the First Star},
  author={Marcelo A. Alvarez and Volker Bromm and Paul R. Shapiro},
  journal={The Astrophysical Journal},
Simulations predict that the first stars in a ΛCDM universe formed at redshifts z > 20 in minihalos with masses of about 106 M☉. We have studied their radiative feedback by simulating the propagation of ionization fronts (I-fronts) created by these first Population III stars (M* = 15-500 M☉) at z = 20, within the density field of a cosmological simulation of primordial star formation, outward through the host minihalo and into the surrounding gas. A three-dimensional ray-tracing calculation… 
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