Following the Cosmic Evolution of Pristine Gas. II. The Search for Pop III–bright Galaxies

Sarmento, Richard; Scannapieco, Evan; Cohen, Seth H.

doi:10.3847/1538-4357/aa989a

Cited by 51 publications

(53 citation statements)

References 118 publications

(137 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A robust prediction from this work, as well as others (e.g. Johnson et al 2013;Pallottini et al 2014;Xu et al 2016a;Sarmento et al 2018), is that Pop III star formation continues at a significant rate (∼ 10 −3 M yr −1 Mpc −3 ) at z 8. While we do not extend our simulation to low enough redshifts to witness its termination, we know that it must end, based on the absence of metal-free star formation in local observations.…”

Section: Termination Of Pop IIIsupporting

confidence: 82%

“…The survival of any pockets of in-falling primordial gas depends on the detailed physics of turbulence-driven mixing of heavy elements (e.g. Smith et al 2015;Sluder et al 2016;Jeon et al 2017;Sarmento et al 2018). Those fine-grained hydrodynamical mixing processes are not resolved here, such that we may overestimate the occurrence of Pop III star formation inside the more massive host haloes.…”

Section: Where Does Pop III Occur?mentioning

confidence: 92%

See 1 more Smart Citation

Legacy of star formation in the pre-reionization universe

Jaacks

Finkelstein

2019

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

We utilize GIZMO, coupled with newly developed sub-grid models for Population III (Pop III) and Population II (Pop II), to study the legacy of star formation in the prereionization Universe. We find that the Pop II star formation rate density (SFRD), produced in our simulation (∼ 10 −2 M yr −1 Mpc −3 at z 10), matches the total SFRD inferred from observations within a factor of < 2 at 7 z 10. The Pop III SFRD, however, reaches a plateau at ∼ 10 −3 M yr −1 Mpc −3 by z ≈ 10, remaining largely unaffected by the presence of Pop II feedback. At z=7.5, ∼ 20% of Pop III star formation occurs in isolated haloes which have never experienced any Pop II star formation (i.e. primordial haloes). We predict that Pop III-only galaxies exist at magnitudes M UV −11, beyond the limits for direct detection with the James Webb Space Telescope (JWST). We assess that our stellar mass function (SMF) and UV luminosity function (UVLF) agree well with the observed low mass/faint-end behavior at z = 8 and 10. However, beyond the current limiting magnitudes, we find that both our SMF and UVLF demonstrate a deviation/turnover from the expected power-law slope (M UV,turn = −13.4 ± 1.1 at z=10). This could impact observational estimates of the true SFRD by a factor of 2(10) when integrating to M UV = −12 (−8) at z ∼ 10, depending on integration limits. Our turnover correlates well with the transition from dark matter haloes dominated by molecular cooling to those dominated by atomic cooling, for a mass M halo ≈ 10 8 M at z 10.

show abstract

Section: Termination Of Pop IIIsupporting

confidence: 82%

Section: Where Does Pop III Occur?mentioning

confidence: 92%

Legacy of star formation in the pre-reionization universe

Jaacks

Finkelstein

2019

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

show abstract

“…We also include LFs from Mason et al (2015) for comparison. fid orig uses the log normal Pop III IMF SEDs from Sarmento et al (2018), while fid uses the Salpeter IMF SEDs. Although the interpretation of surviving SP mass is very different in these two models, the resulting overall LF are nearly indistinguishable.…”

Section: Chemical Compositionmentioning

confidence: 99%

Following the Cosmic Evolution of Pristine Gas. III. The Observational Consequences of the Unknown Properties of Population III Stars

Sarmento

Scannapieco

Côté

2019

ApJ

Self Cite

View full text Add to dashboard Cite

We study the observational consequences of several unknown properties of Population III (Pop III) stars using large-scale cosmological simulations that include a subgrid model to track the unresolved mixing of pollutants. Varying the value of the critical metallicity that marks the boundary between Pop III and Population II (Pop II) star formation across 2 dex has a negligible effect on the fraction of Pop III stars formed and the subsequent fraction of Pop III flux from high-redshift galaxies. However, adopting a log normal initial mass function (IMF) for Pop III stars, in place of a baseline Salpeter IMF, results in a Pop III star formation rate density (SFRD) that is 1/4 of the baseline rate. The flux from high-redshift galaxies modeled with this IMF is highly bimodal, resulting in a tiny fraction of z ≤ 8 galaxies with more than 75% of their flux coming from Pop III stars. However, at z = 9, right before reionization in our simulations, ≈ 20% of galaxies are Pop III-bright with m UV ≤ 31.4 mag and at least 75% of their flux generated by Pop III stars . Additionally, the log normal Pop III IMF results in a population of carbon enhanced, metal poor stars in reasonable agreement with MW halo observations. Our analysis supports the conclusion that the Pop III IMF was dominated by stars in the 20-120 M range that generate SN with carbon-enhanced ejecta.

show abstract

“…Mixing timescales are likely proportional to the eddy turnover times at the injection scale (Pan & Scannapieco 2010;Colbrook et al 2017) and the properties of turbulence in the ISM (Yang & Krumholz 2012;Sarmento et al 2017Sarmento et al , 2018. Mixing within a phase is likely dependent upon the phase's sound speed and velocity dispersion.…”

Section: Physical Interpretation Of the Pdfmentioning

confidence: 99%

Metal Mixing and Ejection in Dwarf Galaxies Are Dependent on Nucleosynthetic Source

Emerick

Bryan

Low

et al. 2018

ApJ

View full text Add to dashboard Cite

Using a high resolution simulation of an isolated dwarf galaxy, accounting for multi-channel stellar feedback and chemical evolution on a star-by-star basis, we investigate how each of 15 metal species are distributed within our multi-phase interstellar medium (ISM) and ejected from our galaxy by galactic winds. For the first time, we demonstrate that the mass fraction probability distribution functions (PDFs) of individual metal species in the ISM are well described by a piecewise log-normal and powerlaw distribution. The PDF properties vary within each ISM phase. Hot gas is dominated by recent enrichment, with a significant power-law tail to high metal fractions, while cold gas is predominately log-normal. In addition, elements dominated by asymptotic giant branch (AGB) wind enrichment (e.g. N and Ba) mix less efficiently than elements dominated by supernova enrichment (e.g. α elements and Fe). This result is driven by the differences in source energetics and source locations, particularly the higher chance compared to massive stars for AGB stars to eject material into cold gas. Nearly all of the produced metals are ejected from the galaxy (only 4% are retained), but over 20% of metals dominated by AGB enrichment are retained. In dwarf galaxies, therefore, elements synthesized predominately through AGB winds should be both overabundant and have a larger spread compared to elements synthesized in either core collapse or Type Ia supernovae. We discuss the observational implications of these results, their potential use in developing improved models of galactic chemical evolution, and their generalization to more massive galaxies.

show abstract

Following the Cosmic Evolution of Pristine Gas. II. The Search for Pop III–bright Galaxies

Cited by 51 publications

References 118 publications

Legacy of star formation in the pre-reionization universe

Legacy of star formation in the pre-reionization universe

Following the Cosmic Evolution of Pristine Gas. III. The Observational Consequences of the Unknown Properties of Population III Stars

Metal Mixing and Ejection in Dwarf Galaxies Are Dependent on Nucleosynthetic Source

Contact Info

Product

Resources

About