Lyman-Werner Escape Fractions from the First Galaxies

Abstract

Direct collapse black holes forming in pristine, atomically-cooling haloes at $z\approx 10-20$ may act as the seeds of supermassive black holes (BH) at high redshifts. In order to create a massive BH seed, the host halo needs to be prevented from forming stars. H${}_2$ therefore needs to be irradiated by a large flux of Lyman-Werner (LW) UV photons in order to suppress H${}_2$ cooling. A key uncertainty in this scenario is the escape fraction of LW radiation from first galaxies, the dominant source of UV photons at this epoch. To better constrain this escape fraction, we have performed radiation-hydrodynamical simulations of the growth of HII regions and their associated photodissociation regions in the first galaxies using the ZEUS-MP code. We find that the LW escape fraction crucially depends on the propagation of the ionisation front (I-front). For an R-type I-front overrunning the halo, the LW escape fraction is always larger than 95%. If the halo recombines later from the outside--in, due to a softened and weakened spectrum, the LW escape fraction in the rest-frame of the halo (the near-field) drops to zero. A detailed and careful analysis is required to analyse slowly moving, D-type I-fronts, where the escape fraction depends on the microphysics and can be as small as 3% in the near-field and 61% in the far-field or as large as 100% in both the near-field and the far-field.

arXiv comment14 pages, 10 figures, 7 tables, accepted for publication in MNRAS

References in corpus (57)

• On the variation of the Initial Mass Function
• Starburst99: Synthesis Models for Galaxies with Active Star Formation
• A luminous quasar at a redshift of z = 7.085
• Seven-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Sky Maps, Systematic Errors, and Basic Results
• Starburst-driven Mass Loss from Dwarf Galaxies: Efficiency and Metal Ejection
• Massive Black Holes as Population III Remnants
• On the properties of massive Population III stars and metal-free stellar populations
• Formation of Supermassive Black Holes by Direct Collapse in Pregalactic Halos
• Formation of the First Supermassive Black Holes
• Formation of Supermassive Black Holes
• Structure of Stationary Photodissociation Fronts
• An ultra-luminous quasar with a twelve-billion-solar-mass black hole at redshift 6.30
• One Hundred First Stars : Protostellar Evolution and the Final Masses
• Supermassive black hole formation during the assembly of pre-galactic discs
• Pair-Instability Supernovae, Gravity Waves, and Gamma-Ray Transients
• The Radiative Feedback of the First Cosmological Objects
• Collapse of Primordial Gas Clouds and the Formation of Quasar Black Holes
• Evidence for PopIII-like stellar populations in the most luminous Lyman-$\alpha$ emitters at the epoch of re-ionisation: spectroscopic confirmation
• The spectral evolution of the first galaxies. I. James Webb Space Telescope detection limits and color criteria for population III galaxies
• The first stars: formation of binaries and small multiple systems
• Radiation Hydrodynamical Evolution of Primordial H II Regions
• Massive black hole seeds from low angular momentum material
• Supermassive Black Hole Formation by Direct Collapse: Keeping Protogalactic Gas H_2--Free in Dark Matter Halos with Virial Temperatures T_vir >~ 10^4 K
• Gravitational fragmentation in turbulent primordial gas and the initial mass function of Population III stars
• Primordial Star Formation under Far-ultraviolet radiation
• Accretion onto the First Stellar Mass Black Holes
• The Structure and Evolution of Early Cosmological HII Regions
• Building up the Population III initial mass function from cosmological initial conditions
• Cosmological Hydrodynamics with Multi-Species Chemistry and Nonequilibrium Ionization and Cooling
• Can Supermassive Black Holes Form in Metal-Enriched High-Redshift Protogalaxies ?
• Ubiquitous seeding of supermassive black holes by direct collapse
• Hyper-Eddington accretion flows onto massive black holes
• Black hole formation in the early universe
• Photodissociation of H2 in Protogalaxies: Modeling Self-Shielding in 3D Simulations
• Zero-metallicity stars I. Evolution at constant mass
• The First Billion Years Project: The escape fraction of ionizing photons in the epoch of reionization
• Predicted UV properties of very metal-poor starburst galaxies
• Rapid growth of seed black holes in the early universe by supra-exponential accretion
• Chemical Evolution in Hierarchical Models Of Cosmic Structure I: Constraints on the Early Stellar Initial Mass Function
• Feedback from Galaxy Formation: Production and Photodissociation of Primordial Molecular Hydrogen
• Origin of Quasar Progenitors from the Collapse of Low-Spin Cosmological Perturbations
• Feedback-regulated Super Massive Black Hole Seed Formation
• Accretion onto Intermediate Mass Black Holes Regulated by Radiative Feedback I. Parametric Study for Spherically Symmetric Accretion
• Confined Population III Enrichment and the Prospects for Prompt Second-Generation Star Formation
• The Formation of Supermassive Black Holes from Low-Mass Pop III Seeds
• Ionization Front Instabilities in Primordial H II Regions
• A Multistep Algorithm for the Radiation Hydrodynamical Transport of Cosmological Ionization Fronts and Ionized Flows
• The First Stars: A Low-Mass Formation Mode
• Suppression of HD-cooling in protogalactic gas clouds by Lyman-Werner radiation
• The Brightest Ly$\alpha$ Emitter: Pop III or Black Hole?
• Detecting Direct Collapse Black Holes: making the case for CR7
• Assessing inflow rates in atomic cooling halos: implications for direct collapse black holes
• Lyman Alpha Signatures from Direct Collapse Black Holes
• Exploring the nature of the Lyman-$\alpha$ emitter CR7
• Lyman-Werner UV Escape Fractions from Primordial Halos
• Boosting Lya and HeII 1640A Line Fluxes from Pop III Galaxies: Stochastic IMF Sampling and Departures from Case-B
• A search for Population III galaxies in CLASH. I. Singly-imaged candidates at high redshift

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• Probing the Small-Scale Matter Power Spectrum with Large-Scale 21-cm Data
• The formation of direct collapse black holes under the influence of streaming velocities
• Cradles of the first stars: self-shielding, halo masses, and multiplicity
• On the formation of the first quasars
• The critical dark matter halo mass for Population III star formation: dependence on Lyman-Werner radiation, baryon-dark matter streaming velocity, and redshift
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• Predicting the locations of possible long-lived low-mass first stars: Importance of satellite dwarf galaxies
• Robust Velocity-induced Acoustic Oscillations at Cosmic Dawn
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• The Ultimately Large Telescope -- what kind of facility do we need to detect Population III stars?
• Modeling Supermassive Primordial Stars with MESA
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• Simulating the UV Escape Fractions from Molecular Cloud Populations in Star-forming Dwarf and Spiral Galaxies
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• The Collapse of Atomically-Cooled Primordial Haloes. I. High Lyman-Werner Backgrounds
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• Population III X-ray Binaries and their Impact on the Early Universe
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• Impact of Population III homogeneous stellar evolution on early cosmic reionisation
• The First Billion Years in Seconds: An Effective Model for the 21-cm Signal with Population III Stars
• The THESAN-ZOOM project: Population III star formation continues until the end of reionization
• Structure of the super-Eddington outflow and itsimpact on the cosmological scale
• Effects of binary stellar populations on direct collapse black hole formation
• Revealing the formation histories of the first stars with the cosmic near-infrared background