Confined Population III Enrichment and the Prospects for Prompt
  Second-Generation Star Formation
  It is widely recognized that nucleosynthetic output of the first, Population
III supernovae was a catalyst defining the character of subsequent stellar
generations. Most of the work on the earliest enrichment was carried out
assuming that the first stars were extremely massive and that the associated
supernovae were unusually energetic, enough to completely unbind the baryons in
the host cosmic minihalo and disperse the synthesized metals into the
intergalactic medium. Recent work, however, suggests that the first stars may
in fact have been somewhat less massive, with a characteristic mass scale of a
few tens of solar masses. We present a cosmological simulation following the
transport of the metals synthesized in a Population III supernova assuming that
it had an energy of 1e51 ergs, compatible with standard Type II supernovae. A
young supernova remnant is inserted in the first star's relic HII region in the
free expansion phase and is followed for 40 Myr employing adaptive mesh
refinement and Lagrangian tracer particle techniques. The supernova remnant
remains partially trapped within the minihalo and the thin snowplow shell
develops pronounced instability and fingering. Roughly half of the ejecta turn
around and fall back toward the center of the halo, with 1% of the ejecta
reaching the center in 30 kyr and 10% in 10 Myr. The average metallicity of the
combined returning ejecta and the pristine filaments feeding into the halo
center from the cosmic web is 0.001 - 0.01 Z_sun, but the two remain unmixed
until accreting onto the central hydrostatic core that is unresolved at the end
of the simulation. We conclude that if Population III stars had less extreme
masses, they promptly enriched the host minihalos with metals and triggered
Population II star formation.
