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Title: 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≲ 3kpc. 7 and 17% of regions haver> 7 kpc for metal-rich and ionized radii, respectively. We find that the metallicity distribution function of second-generation stars overlaps that of subsequent Population II star formation, spanning metal-deficient (∼7.94 × 10−8Z) to supersolar (∼3.71Z), and that 30.5% of second-generation stars haveZ> 10−2Z. We find that the metallicity of second-generation stars depends on progenitor configuration, with metals from pair-instability supernovae contributing to the most metal-rich clusters; these clusters form promptly after the supernova event. Finally, we create an interpretable regression model to predict the radius of the metal-rich influence of Population III star systems within the first 7–18 Myr after the first Population III stars form in the region.

 
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Award ID(s):
2108020 2108076
PAR ID:
10486105
Author(s) / Creator(s):
;
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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