Lyman Radiation Hydrodynamics of Turbulent H II Regions in Molecular Clouds: A Physical Origin of LyC Leakage and the Associated Ly$\alpha$ Spectra

Abstract

We examine Lyman continuum (LyC) leakage through H II regions regulated by turbulence and radiative feedback in a giant molecular cloud in the context of fully-coupled radiation hydrodynamics (RHD). The physical relations of the LyC escape with H I covering fraction, kinematics, spectral hardness, and the emergent Lyman-$\alpha$ (Ly$\alpha$) line profiles are studied using a series of RHD turbulence simulations performed with RAMSES-RT. The turbulence-regulated mechanism allows ionizing photons to leak out at early times before the onset of supernova feedback. The LyC photons escape through turbulence-generated low column density channels which are evacuated efficiently by radiative feedback via photoheating-induced shocks across the D-type ionization fronts. Ly$\alpha$ photons funnel through the photoionized channels along the paths of LyC escape, resulting in a diverse Ly$\alpha$ spectral morphology including narrow double-peaked profiles. The Ly$\alpha$ peak separation is controlled by the residual H I column density of the channels and the line asymmetry correlates with the porosity and multiphase structure of the H II region. This mechanism through the turbulent H II regions can naturally reproduce the observed Ly$\alpha$ spectral characteristics of some of LyC-leaking galaxies. This RHD turbulence-origin provides an appealing hypothesis to explain high LyC leakage from very young ($\sim 3$ Myr) star-forming galaxies found in the local Universe without need of extreme galactic outflows nor supernova feedback. We discuss the implications of the turbulent H II regions on other nebular emission lines and a possible observational test with the Magellanic System and local blue compact dwarf galaxies as analogs of reionization-era systems.

arXiv comment23 pages, 17 figures, 2 tables, submitted to ApJ

References in corpus (164)

• Astropy: A Community Python Package for Astronomy
• The Astropy Project: Building an inclusive, open-science project and status of the v2.0 core package
• Star Formation in the Milky Way and Nearby Galaxies
• Dust Grain Size Distributions and Extinction in the Milky Way, LMC, and SMC
• Theory of Star Formation
• Cosmological Hydrodynamics with Adaptive Mesh Refinement: a new high resolution code called RAMSES
• UV Luminosity Functions at redshifts z~4 to z~10: 10000 Galaxies from HST Legacy Fields
• A General Theory of Turbulence-Regulated Star Formation, From Spirals to ULIRGs
• Binary Population and Spectral Synthesis Version 2.1: construction, observational verification and new results
• Cosmic Reionization and Early Star-Forming Galaxies: A Joint Analysis of New Constraints from Planck and Hubble Space Telescope
• Comparing the statistics of interstellar turbulence in simulations and observations: Solenoidal versus compressive turbulence forcing
• The Star Formation Rate of Turbulent Magnetized Clouds: Comparing Theory, Simulations, and Observations
• Gas-to-Dust mass ratios in local galaxies over a 2 dex metallicity range
• The Statistics of Supersonic Isothermal Turbulence
• 3D Lyman-alpha radiation transfer. I. Understanding Lyman-alpha line profile morphologies
• The Birth of a Galaxy - III. Propelling reionisation with the faintest galaxies
• The Dearth of z~10 Galaxies in all HST Legacy Fields -- The Rapid Evolution of the Galaxy Population in the First 500 Myr
• Low-Resolution Spectroscopy of Gamma-ray Burst Optical Afterglows: Biases in the Swift Sample and Characterization of the Absorbers
• Escape fraction of ionizing photons during reionization: effects due to supernova feedback and runaway OB stars
• Detection of high Lyman continuum leakage from four low-redshift compact star-forming galaxies
• RAMSES-RT: Radiation hydrodynamics in the cosmological context
• Low-redshift Lyman continuum leaking galaxies with high [OIII]/[OII] ratios
• The Keck Lyman Continuum Spectroscopic Survey (KLCS): The Emergent Ionizing Spectrum of Galaxies at $z\sim 3$
• Rest-frame ultraviolet-to-optical spectral characteristics of extremely metal-poor and metal-free galaxies
• The Big Problems in Star Formation: the Star Formation Rate, Stellar Clustering, and the Initial Mass Function
• Lyman Alpha Radiation From Collapsing Protogalaxies I: Characteristics of the Emergent Spectrum
• Massive stars in massive clusters II: Disruption of bound clusters by photoionization
• Radiation Hydrodynamical Evolution of Primordial H II Regions
• On the universality of supersonic turbulence
• Using Lyman-alpha to detect galaxies that leak Lyman continuum
• Extreme Feedback and the Epoch of Reionization: Clues in the Local Universe
• The SPHINX Cosmological Simulations of the First Billion Years: the Impact of Binary Stars on Reionization
• Escape of Ionizing Radiation from High Redshift Galaxies
• The Magellanic Mopra Assessment (MAGMA). I. The Molecular Cloud Population of the Large Magellanic Cloud
• Ly$\alpha$ emission from Green Peas: the role of circumgalactic gas density, covering, and kinematics
• J1154+2443: a low-redshift compact star-forming galaxy with a 46 per cent leakage of Lyman continuum photons
• Lyman Alpha Radiative Transfer in a Multi-Phase Medium
• Modeling UV Radiation Feedback from Massive Stars: II. Dispersal of Star-Forming Giant Molecular Clouds by Photoionization and Radiation Pressure
• Green Pea Galaxies and cohorts: Luminous Compact Emission-Line Galaxies in the Sloan Digital Sky Survey
• Fluctuating feedback-regulated escape fraction of ionizing radiation in low-mass, high-redshift galaxies
• Cosmological simulations of the circumgalactic medium with 1 kpc resolution: enhanced HI column densities
• Lyman-alpha spectral properties of five newly discovered Lyman continuum emitters
• Detection of the Far-infrared [O III] and Dust Emission in a Galaxy at Redshift 8.312: Early Metal Enrichment in the Heart of the Reionization Era
• Systematic Identification of LAEs for Visible Exploration and Reionization Research Using Subaru HSC (SILVERRUSH). I. Program Strategy and Clustering Properties of ~2,000 Lya Emitters at z=6-7 over the 0.3-0.5 Gpc${}^2$ Survey Area
• What Drives the Expansion of Giant HII Regions?: A Study of Stellar Feedback in 30 Doradus
• The First Billion Years Project: The escape fraction of ionizing photons in the epoch of reionization
• ALMA Reveals the Molecular Medium Fueling the Nearest Nuclear Starburst
• Feedback from Winds and Supernovae in Massive Stellar Clusters. I: Hydrodynamics
• Spectroscopic Confirmation of Three Redshift 5.7 Lyman-alpha Emitters from the Large Area Lyman Alpha Survey
• The Impact of Enhanced Halo Resolution on the Simulated Circumgalactic Medium
• A scheme for radiation pressure and photon diffusion with the M1 closure in RAMSES-RT
• The Global Evolution of Giant Molecular Clouds. I: Model Formulation and Quasi-Equilibrium Behavior
• Ly$\alpha$ profile, dust, and prediction of Ly$\alpha$ escape fraction in Green Pea Galaxies
• Radiation-Hydrodynamic Simulations of the Formation of Orion-Like Star Clusters II. The Initial Mass Function from Winds, Turbulence, and Radiation
• A Local Clue to the Reionization of the Universe
• The Escape of Ionizing Photons from the Galaxy
• The spectral evolution of the first galaxies. II. Spectral signatures of Lyman continuum leakage from galaxies in the reionization epoch
• The Lyman Continuum Escape Survey: Ionizing Radiation from [O III]-Strong Sources at a Redshift of 3.1
• The Optical Depth of H II Regions in the Magellanic Clouds
• Ultraviolet spectra of extreme nearby star-forming regions --- approaching a local reference sample for JWST
• Monte Carlo Simulation of Lyman Alpha Scattering and Application to Damped Lyman Alpha Systems
• Is Turbulence in the Interstellar Medium Driven by Feedback or Gravity? An Observational Test
• Dynamical Expansion of Ionization and Dissociation Front around a Massive Star. II. On the Generality of Triggered Star Formation
• Lyman alpha Radiative Transfer with Dust: Escape Fractions from Simulated High-Redshift Galaxies
• Radiation-magnetohydrodynamic simulations of HII regions and their associated PDRs in turbulent molecular clouds
• Driving Turbulence and Triggering Star Formation by Ionizing Radiation
• The Role of Stellar Feedback in the Dynamics of HII Regions
• Nearly all the sky is covered by Lyman-alpha emission around high redshift galaxies
• The Difficulty of Getting High Escape Fractions of Ionizing Photons from High-redshift Galaxies: a View from the FIRE Cosmological Simulations
• The LyA-LyC Connection: Evidence for an Enhanced Contribution of UV-faint Galaxies to Cosmic Reionization
• The VLT-FLAMES Tarantula Survey - XI. A census of the hot luminous stars and their feedback in 30 Doradus
• Binary Stars Can Provide the "Missing Photons" Needed for Reionization
• Dissecting the Circumstellar Environment of Gamma-Ray Burst Progenitors
• The Lyman alpha Reference Sample: II. HST imaging results, integrated properties and trends
• Magnetohydronamic Evolution of HII Regions in Molecular Clouds: Simulation Methodology, Tests, and Uniform Media
• The production and escape of Lyman-Continuum radiation from star-forming galaxies at z~2 and their redshift evolution
• Dynamical HII Region Evolution in Turbulent Molecular Clouds
• Keck Spectroscopy of Gravitationally Lensed z=4 Galaxies: Improved Constraints on the Escape Fraction of Ionizing Photons
• The Connection Between Reddening, Gas Covering Fraction, and the Escape of Ionizing Radiation at High Redshift
• The Global Evolution of Giant Molecular Clouds II: The Role of Accretion
• SILVERRUSH. V. Census of Lya, [OIII]5007, Ha, and [CII]158um Line Emission with ~1000 LAEs at z=4.9-7.0 Revealed with Subaru/HSC
• The Lyman-alpha Reference Sample: I. Survey outline and first results for Markarian 259
• Accurately predicting the escape fraction of ionizing photons using restframe ultraviolet absorption lines
• Detailed Numerical Simulations on the Formation of Pillars around HII-regions
• Accretion-Driven Turbulence and the Transition to Global Instability in Young Galaxy Disks
• A Model for (Non-Lognormal) Density Distributions in Isothermal Turbulence
• A Deep Hubble and Keck Search for Definitive Identification of Lyman Continuum Emitters at z~3.1
• Adiabatic Heating of Contracting Turbulent Fluids
• The physics of Lyman-alpha escape from high-redshift galaxies
• A new density variance - Mach number relation for subsonic and supersonic, isothermal turbulence
• Green Pea Galaxies Reveal Secrets of Ly$\alpha$ Escape
• A Hard Ionizing Spectrum in z=3-4 Ly-alpha Emitters with Intense [OIII] Emission: Analogs of Galaxies in the Reionization Era?
• A systematic study of Lyman-Alpha transfer through outflowing shells: Model parameter estimation
• A method for reconstructing the variance of a 3D physical field from 2D observations: Application to turbulence in the ISM
• Neutral gas properties of Lyman continuum emitting galaxies: column densities and covering fractions from UV absorption lines
• A New Constraint on the Escape Fraction in Distant Galaxies Using Gamma-ray Burst Afterglow Spectroscopy
• Probing Cosmic Dawn with Emission Lines: Predicting Infrared and Nebular Line Emission for ALMA and JWST
• Feedback in Clouds II: UV Photoionisation and the first supernova in a massive cloud
• Ionization Front Instabilities in Primordial H II Regions
• Evidence for Large-Scale Fluctuations in the Metagalactic Ionizing Background Near Redshift Six
• Linking Ly-alpha and Low-Ionization Transitions at Low Optical Depth
• Photoionisation Feedback in a Self-Gravitating, Magnetised, Turbulent Cloud
• Sub-Eddington Star-Forming Regions are Super-Eddington: Momentum Driven Outflows from Supersonic Turbulence
• Do galaxies that leak ionizing photons have extreme outflows?
• The Aurora radiation-hydrodynamical simulations of reionization: calibration and first results
• Disruption of Molecular Clouds by Expansion of Dusty H II Regions
• The Metagalactic Ionizing Background: A Crisis in UV Photon Production or Incorrect Galaxy Escape Fractions?
• The Lyman-alpha signature of the first galaxies
• The fraction of ionizing radiation from massive stars that escapes to the intergalactic medium
• Puzzling Lyman-alpha line profiles in green pea galaxies
• Ly$\alpha$-Lyman Continuum connection in 3.5 < z < 4.3 star-forming galaxies from the VUDS survey
• Feedback from massive stars at low metallicities: MUSE observations of N44 and N180 in the Large Magellanic Cloud
• Revisiting the Lyman Continuum Escape Crisis: Predictions for z > 6 from Local Galaxies
• A Low Lyman Continuum Escape Fraction of $<10\%$ for Extreme [OIII] Emitters in an Overdensity at z$\sim 3.5$
• The Role of Galaxies and AGN in Reionising the IGM - I: Keck Spectroscopy of 5 < z < 7 Galaxies in the QSO Field J1148+5251
• Escape of Lyman-alpha and continuum photons from star-forming galaxies
• From Mirrors to Windows: Lyman-Alpha Radiative Transfer in a Very Clumpy Medium
• Spatially adaptive radiation-hydrodynamical simulations of galaxy formation during cosmological reionization
• Age, size, and position of H ii regions in the Galaxy. Expansion of ionized gas in turbulent molecular clouds
• Directional Lya equivalent boosting I. Spherically symmetric distributions of clumps
• The spectral evolution of the first Galaxies. III. Simulated James Webb Space Telescope spectra of reionization-epoch galaxies with Lyman continuum leakage
• Resonant line transfer in a fog: Using Lyman-alpha to probe tiny structures in atomic gas
• Kinematics and Optical Depth in the Green Peas: Suppressed Superwinds in Candidate LyC Emitters
• A method for reconstructing the PDF of a 3D turbulent density field from 2D observations
• The Lyman Continuum Escape Fraction of The Cosmic Horseshoe: A Test of Indirect Estimates
• Three-Dimensional Dynamical Instabilities in Galactic Ionization Fronts
• Impact of Lyman alpha pressure on metal-poor dwarf galaxies
• On the Lack of Correlation Between [OIII]/[OII] and Lyman-Continuum Escape Fraction
• New constraints on the average escape fraction of Lyman continuum radiation in z~4 galaxies from the VIMOS Ultra Deep Survey (VUDS)
• Lyman Alpha Driven Outflows Around Star Forming Galaxies
• On the Origin of Diffuse Ionized Gas in the Antennae Galaxy
• Lyman-alpha radiation hydrodynamics of galactic winds before cosmic reionization
• Radiative Rayleigh-Taylor instabilities
• Lyman Alpha Signatures from Direct Collapse Black Holes
• Absorption Line Spectroscopy of Gravitationally-Lensed Galaxies: Further Constraints on the Escape Fraction of Ionizing Photons at High Redshift
• The Lyman Continuum Escape and ISM properties in Tololo 1247-232 - New Insights from HST and VLA
• Time-dependent excitation and ionization modelling of absorption-line variability due to GRB 080310
• The Power Spectrum of the Lyman-$\alpha$ Forest at z < 0.5
• The role of galaxies and AGN in reionizing the IGM - II: metal-tracing the faint sources of reionization at $5\lesssim z\lesssim 6$
• The Lyman Alpha Reference Sample: III. Properties of the Neutral ISM from GBT and VLA Observations
• Neutral Gas Properties and Ly$\alpha$ Escape in Extreme Green Pea Galaxies
• Warm Ionized Gas Revealed in the Magellanic Bridge Tidal Remnant: Constraining the Baryon Content and the Escaping Ionizing Photons around Dwarf Galaxies
• The impact of Stellar feedback from velocity-dependent ionised gas maps. -- A MUSE view of Haro 11
• Instabilities in the Envelopes and Winds of Very Massive Stars
• Non-linear Evolution of Rayleigh-Taylor Instability in a Radiation Supported Atmosphere
• Simulating the UV Escape Fractions from Molecular Cloud Populations in Star-forming Dwarf and Spiral Galaxies
• The Molecular Clouds Fueling a 1/5 Solar Metallicity Starburst
• The Escape Fraction of Ionizing Radiation from Galaxies
• Acceleration of Galactic Supershells by Lyman Alpha Radiation
• Small-scale Intensity Mapping: Extended Halos as a Probe of the Ionizing Escape Fraction and Faint Galaxy Populations during Reionization
• The Effect of Turbulence on Nebular Emission Line Ratios
• The HI content of extremely metal-deficient blue compact dwarf galaxies
• Unlocking the Full Potential of Extragalactic Ly$\alpha$ through Its Polarization Properties
• Cosmic Reionization On Computers: Numerical and Physical Convergence
• ALMA Observations toward the starburst dwarf galaxy NGC 5253: I. Molecular cloud properties and scaling relations
• The imprint of cosmic ray driven outflow on Lyman-alpha spectra
• Ultra Violet Escape Fractions from Giant Molecular Clouds During Early Cluster Formation
• Dense Regions in Supersonic Isothermal Turbulence
• A new model framework for circumgalactic Ly$\alpha$ radiative transfer constrained by galaxy-Ly$\alpha$ forest clustering
• Rayleigh-Taylor instability of ionization front around black holes
• The Impact of Unresolved Turbulence on the Escape Fraction of Lyman Continuum Photons
• Detection of HI in Emission in the Lyman Alpha Emitting Galaxy Haro 11
• Blue Wings and Bumps via Fermi-like Acceleration of Lyman-alpha photons across Shocks
• Radiation Hydrodynamical Instabilities in Cosmological and Galactic Ionization Fronts

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