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Abstract We investigate how stellar feedback from the first stars (Population III) distributes metals through the interstellar and intergalactic medium using the star-by-star cosmological hydrodynamics simulation, Aeos. We find that energy injected from the supernovae (SNe) of the first stars is enough to expel a majority of gas and injected metals beyond the virial radius of halos with massMdm ≲ 107M⊙, regardless of the number of SNe. This prevents self-enrichment and results in a nonmonotonic increase in metallicity at early times. Most minihalos (Mdm ≳ 105M⊙) do not retain significant fractions of the yields produced within their virial radii until they have grown to halo masses ofMdm ≳ 107M⊙. The loss of metals to regions well beyond the virial radius delays the onset of enriched star formation and extends the period that Population III star formation can persist. We also explore the contributions of different nucleosynthetic channels to 10 individual elements. On the timescale of the simulation (lowest redshiftz= 14.3), enrichment is dominated by core-collapse supernovae for all elements, but with a significant contribution from asymptotic giant branch winds to thes-process elements, which are normally thought to only be important at late times. In this work, we establish important mechanisms for early chemical enrichment, which allows us to apply Aeosin later epochs to trace the evolution of enrichment during the complete transition from Population III to Population II stars.
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Connecting Primordial Star-forming Regions and Second-generation Star Formation in the Phoenix Simulations
Abstract We introduce the Phoenix Simulations, a suite of highly resolved cosmological simulations featuring hydrodynamics, primordial gas chemistry, primordial and enriched star formation and feedback, UV radiative transfer, and saved outputs with Δt= 200 kyr. We observe 73,523 individual primordial stars within 3313 distinct regions forming 2110 second-generation enriched star clusters byz≥ 12 within a combined 177.25 Mpc3volume across three simulations. The regions that lead to enriched star formation can contain ≳150 primordial stars, with 80% of regions having experienced combinations of primordial Type II, hypernovae, and/or pair-instability supernovae. Primordial supernovae enriched 0.8% of the volume, with 2% of enriched gas enriched by later-generation stars. We determine the extent of a primordial stellar region by its metal-rich or ionized hydrogen surrounding cloud; the metal-rich and ionized regions have time-dependent average radiir≲ 3
- PAR ID:
- 10486105
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 932
- Issue:
- 1
- ISSN:
- 0004-637X
- Format(s):
- Medium: X Size: Article No. 71
- Size(s):
- Article No. 71
- Sponsoring Org:
- National Science Foundation
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