Wouthuysen-Field coupling strength and application to high-redshift 21 cm radiation

Abstract

The first UV sources in the universe are expected to have coupled the HI spin temperature to the gas kinetic temperature via scattering in the Lyman-alpha resonance [the Wouthuysen-Field (WF) effect]. By establishing an HI spin temperature different from the temperature of the CMB, the WF effect should allow observations of HI during the reionization epoch in the redshifted 21 cm line. This paper investigates four mechanisms that can affect the strength of the WF effect that were not previously considered: (1) Photons redshifting into the HI Lyman resonances may excite an H atom and result in a radiative cascade terminating in two-photon 2s->1s emission, rather than always degrading to Lyman-alpha as usually assumed. (2) The fine structure of the Lyman-alpha resonance alters the photon frequency distribution and leads to a suppression of the scattering rate. (3) The spin-flip scatterings change the frequency of the photon and cause the photon spectrum to relax not to the kinetic temperature of the gas but to a temperature between the kinetic and spin temperatures, effectively reducing the strength of the Wouthuysen-Field coupling. (4) Near line centre, a photon can change its frequency by several times the line width in a single scattering event, thus potentially invalidating the usual calculation of the Lyman-alpha spectral distortion based on the diffusion approximation. It is shown that (1) suppresses the WF coupling strength by a factor of up to ~2, while (2) and (3) are important only at low kinetic temperatures. Effect (4) has a <=3% effect for kinetic temperatures T_k>=2K. If the pre-reionization IGM was efficiently heated by X-rays, only effect (1) is important. Fitting formulae are provided for the range of T_k>=2K and Gunn-Peterson optical depth 10^5--10^7. [ABRIDGED]

17 pages, 7 figures, MNRAS accepted version

References in corpus (5)

• Cosmological parameter analysis including SDSS Ly-alpha forest and galaxy bias: constraints on the primordial spectrum of fluctuations, neutrino mass, and dark energy
• Detecting the Earliest Galaxies Through Two New Sources of 21cm Fluctuations
• A Method for Separating the Physics from the Astrophysics of High-Redshift 21cm Fluctuations
• The CMBR fluctuations from HI perturbations prior to reionization
• Nonlinear clustering during the cosmic Dark Ages and its effect on the 21-cm background from minihalos

Cited by in corpus (213)

• Cosmology at Low Frequencies: The 21 cm Transition and the High-Redshift Universe
• 21-cm cosmology
• Observational constraints on Cosmic Reionization
• 21cmFAST: A Fast, Semi-Numerical Simulation of the High-Redshift 21-cm Signal
• Possible interaction between baryons and dark-matter particles revealed by the first stars
• Fundamental Physics with the Square Kilometre Array
• Reionization and the Cosmic Dawn with the Square Kilometre Array
• The Global 21 Centimeter Background from High Redshifts
• New Limits on 21cm EoR From PAPER-32 Consistent with an X-Ray Heated IGM at z=7.7
• 21 cm fluctuations from inhomogeneous X-ray heating before reionization
• PAPER-64 Constraints on Reionization: The 21cm Power Spectrum at z=8.4
• Signs of Dark Matter at 21-cm?
• Simulating Cosmic Reionization at Large Scales II: the 21-cm Emission Features and Statistical Signals
• The observable signature of late heating of the Universe during cosmic reionization
• Evolution of the 21 cm signal throughout cosmic history
• Impact of the Relative Motion between the Dark Matter and Baryons on the First Stars
• What does the first highly-redshifted 21-cm detection tell us about early galaxies?
• HERA Phase I Limits on the Cosmic 21-cm Signal: Constraints on Astrophysics and Cosmology During the Epoch of Reionization
• Fast Large Volume Simulations of the 21 cm Signal from the Reionization and pre-Reionization Epochs
• Heating of Baryons due to Scattering with Dark Matter During the Dark Ages
• The Global 21-cm Signal in the Context of the High-z Galaxy Luminosity Function
• 21cm Limits on Decaying Dark Matter and Primordial Black Holes
• Descending from on high: Lyman series cascades and spin-kinetic temperature coupling in the 21 cm line
• The Effects of Dark Matter Decay and Annihilation on the High-Redshift 21 cm Background
• The Impact of the First Galaxies on Cosmic Dawn and Reionization
• Eliminating the optical depth nuisance from the CMB with 21 cm cosmology
• Secondary ionization and heating by fast electrons
• The Rise of the First Stars: Supersonic Streaming, Radiative Feedback, and 21-cm Cosmology
• Primordial non-gaussianity from the bispectrum of 21-cm fluctuations in the dark ages
• 21 cm signal from cosmic dawn: Imprints of spin temperature fluctuations and peculiar velocities
• The Evolution of 21-cm Structure (EOS): public, large-scale simulations of Cosmic Dawn and Reionization
• Constraining primordial black holes as dark matter using the global 21-cm signal with X-ray heating and excess radio background
• Light cone effect on the reionization 21-cm power spectrum
• The Imprint of Warm Dark Matter on the Cosmological 21-cm Signal
• Cosmic Reionization and the 21-cm signal: Comparison between an analytical model and a simulation
• Constraining Non-Cold Dark Matter Models with the Global 21-cm Signal
• Probing the Small-Scale Matter Power Spectrum with Large-Scale 21-cm Data
• Decoding the X-ray Properties of Pre-Reionization Era Sources
• The Physics and Early History of the Intergalactic Medium
• The Scattering of Lyman-series Photons in the Intergalactic Medium
• Intensity Mapping across Cosmic Times with the Lyman-Alpha Line
• Constraining DM through 21 cm observations
• A tale of two sites -- I: Inferring the properties of minihalo-hosted galaxies from current observations
• Primordial helium recombination I: feedback, line transfer, and continuum opacity
• Heating of the intergalactic medium by the cosmic microwave background during cosmic dawn
• The subtlety of Ly-a photons: changing the expected range of the 21-cm signal
• Unveiling the nature of dark matter with high redshift 21 cm line experiments
• A new light on 21 cm intensity fluctuations from the dark ages
• Towards a measurement of the spectral runnings
• The 21cm Signature of the First Stars
• The Effects of Population III X-ray and Radio Backgrounds on the Cosmological 21-cm Signal
• The nature of dark matter from the global high redshift HI 21 cm signal
• Dawn of the dark: unified dark sectors and the EDGES Cosmic Dawn 21-cm signal
• Robust Velocity-induced Acoustic Oscillations at Cosmic Dawn
• Spin Exchange Rates in Electron-Hydrogen Collisions
• The Implications of a Pre-reionization 21 cm Absorption Signal for Fuzzy Dark Matter
• The 21 cm signal and the interplay between dark matter annihilations and astrophysical processes
• Unique Signatures of Population III Stars in the Global 21-cm Signal
• A Standard Ruler at Cosmic Dawn
• UV pumping of hyperfine transitions in the light elements, with application to 21-cm hydrogen and 92-cm deuterium lines from the early universe
• Heating and cooling of the intergalactic medium by resonance photons
• Introducing SPHINX-MHD: The Impact of Primordial Magnetic Fields on the First Galaxies, Reionization, and the Global 21cm Signal
• A fresh look into the interacting dark matter scenario
• The Radio Scream from Black Holes at Cosmic Dawn: A Semi-Analytic Model for the Impact of Radio Loud Black-Holes on the 21 cm Global Signal
• Lyman Alpha Driven Outflows Around Star Forming Galaxies
• Charting the Parameter Space of the 21-cm Power Spectrum
• Lyman-$\alpha$ coupling and heating at Cosmic Dawn
• The Energy Cascade from Warm Dark Matter Decays
• Fluctuations in the High-Redshift Lyman-Werner and Lyman-alpha Radiation Backgrounds
• Ruling out 3 keV warm dark matter using 21 cm-EDGES data
• An Effective Model for the Cosmic-Dawn 21-cm Signal
• Influence of primordial magnetic fields on 21 cm emission
• The impact of spin temperature fluctuations on the 21-cm moments
• A limit on the warm dark matter particle mass from the redshifted 21 cm absorption line
• Closing the window on fuzzy dark matter with the 21cm signal
• Recognizing the First Radiation Sources Through Their 21-cm Signature
• Lyman-alpha transfer in primordial hydrogen recombination
• Redshifted 21 Centimeter Emission from Minihalos Before Reionization
• 21SSD: a public database of simulated 21-cm signals from the epoch of reionization
• Dark Matter microphysics and 21 cm observations
• Interpreting the Global 21-cm Signal from High Redshifts. I. Model Independent Constraints
• Minimum size of 21-cm simulations
• The 21 Centimeter Forest
• Primordial magnetic fields and the HI signal from the epoch of reionization
• Les Houches Lectures on Indirect Detection of Dark Matter
• Improved Fokker-Planck Equation for Resonance Line Scattering
• Probing the effects of primordial black holes on 21-cm EDGES signal along with interacting dark energy and dark matter - baryon scattering
• Impact of Dark Matter Annihilation on the High-Redshift Intergalactic Medium
• The 21-cm Line as a Probe of Reionization
• Dark stars: Implications and constraints from cosmic reionization and extragalactic background radiation
• Impact of Ly$\alpha$ heating on the global 21-cm signal from the Cosmic Dawn
• Redshifted 21-cm bispectrum II: Impact of the spin temperature fluctuations and redshift space distortions on the signal from the Cosmic Dawn
• Lyalpha versus X-ray heating in the high-z IGM
• He II absorption and the sawtooth spectrum of the cosmic far-UV background
• First Constraints on Small-Scale Non-Gaussianity from UV Galaxy Luminosity Functions
• Spatially Extended 21 cm Signal from Strongly Clustered UV and X-Ray Sources in the Early Universe
• Signatures of clumpy dark matter in the global 21 cm background signal
• A self-consistent semi-analytic model for Population III star formation in minihalos
• Detecting Early Galaxies Through Their 21-cm Signature
• The role of soft photon injection and heating in 21 cm cosmology
• Constraints on Early Star Formation from the 21-cm Global Signal
• Radiative Transfer Effect on Ultraviolet Pumping of the 21cm Line in the High Redshift Universe
• The Spin-Resolved Atomic Velocity Distribution and 21-cm Line Profile of Dark-Age Gas
• Particle energy cascade in the Intergalactic Medium
• CMB and 21-cm Signals for Dark Matter with a Long-Lived Excited State
• Probing high-redshift galaxies with Ly$\alpha$ intensity mapping
• A hint on the metal-free star formation rate density from 21cm-EDGES data
• Violation of statistical isotropy and homogeneity in the 21-cm power spectrum
• Energy transfer by the scattering of resonant photons
• Bounds on abundance of primordial black hole and dark matter from EDGES 21-cm signal
• Probing ultra-light axions with the 21-cm Signal during Cosmic Dawn
• The Effects of Rayleigh Scattering on the CMB and Cosmic Structure
• Probing the first galaxies with the SKA
• 21cm signal sensitivity to dark matter decay
• ETHOS -- An Effective Theory of Structure Formation: Impact of Dark Acoustic Oscillations on Cosmic Dawn
• Structure Formation and the Global 21-cm Signal in the Presence of Coulomb-like Dark Matter-Baryon Interactions
• Absorption by Spinning Dust: a Contaminant for High-Redshift 21 cm Observations
• Distinctive rings in the 21 cm signal of the epoch of reionization
• Detecting the 21 cm Forest in the 21 cm Power Spectrum
• Lyalpha heating and its impact on early structure formation
• Exploring circular polarization in the CMB due to conventional sources of cosmic birefringence
• Cosmic Reionization May Still Have Started Early and Ended Late: Confronting Early Onset with CMB Anisotropy and 21 cm Global Signals
• Redshifted intergalactic 3He+ 8.7 GHz hyperfine absorption
• Radiative transfer effects in primordial hydrogen recombination
• Probing large scale filaments with HI and ${}^3$HeII
• Quasars as probes of cosmological reionization
• Constraint on Primordial Magnetic Fields In the Light of ARCADE 2 and EDGES Observations
• Can the 21 cm signal probe Population III and II star formation?
• Weak Gravitational Lensing of High-Redshift 21 cm Power Spectra
• 21cmfish: Fisher-matrix framework for fast parameter forecasts from the cosmic 21-cm signal
• Detailed modelling of the 21-cm Forest
• X-rays and hard UV radiation From the First Galaxies: Ionization Bubbles and 21 cm Observations
• The role of Pop III stars and early black holes in the 21cm signal from Cosmic Dawn
• Detectable Signatures of Cosmic Radiative Feedback
• Detection and Fundamental Applications of Individual First Galaxies
• The Wouthuysen Field Absorption Trough in Cosmic Strings Wakes
• Cosmological implications of the composite spectra of galactic X-ray binaries constructed using MAXI data
• The detectability of strong 21 centimetre forest absorbers from the diffuse intergalactic medium in late reionisation models
• 21cmFirstCLASS I. Cosmological tool for $\Lambda$CDM and beyond
• Distinctive 21 cm structures of the first stars, galaxies, and quasars
• Exploring the cosmic dawn and epoch of reionization with 21cm line
• Can accreting primordial black holes explain the excess radio background?
• New probe of magnetic fields in the prereionization epoch. I. Formalism
• EDGES result versus CMB and low-redshift constraints on ionization histories
• Variations in fundamental constants at the cosmic dawn
• Ly-alpha Radiative Transfer: A Stokes Vector Approach to Ly-alpha Polarization
• Measuring the cosmic expansion rate using 21-cm velocity acoustic oscillations
• Lyman-$\alpha$ feedback prevails at Cosmic Dawn: Implications for the first galaxies, stars, and star clusters
• Accurate modelling of the Lyman-$\alpha$ coupling for the 21-cm signal, observability with NenuFAR and SKA
• Probing Compensated Isocurvature with the 21-cm Signal during Cosmic Dawn
• The Global 21 cm Absorption from Cosmic Dawn with Inhomogeneous Gas Distribution
• The First Billion Years in Seconds: An Effective Model for the 21-cm Signal with Population III Stars
• Enlightening the dark ages with dark matter
• 3-cm Fine Structure Masers: A Unique Signature of Supermassive Black Hole Formation via Direct Collapse in the Early Universe
• Edges and Endpoints in 21-cm Observations from Resonant Photon Production
• Exploring multimessenger signals from heavy dark matter decay with EDGES 21-cm result and IceCube
• EDGES signal in presence of magnetic fields
• Constraining structure formation using EDGES
• Detecting primordial gravitational waves with circular polarization of the redshifted 21 cm line: I. Formalism
• Global 21-cm brightness temperature in viscous dark energy models
• Time evolution of Wouthuysen-Field coupling
• Astrophysics in 2006
• Radio views of cosmic reionization
• Dark Matter annihilation energy output and its effects on the high-z IGM
• Dark Matter Annihilation in the Circumgalactic Medium at High Redshifts
• The validity of 21 cm spin temperature as a kinetic temperature indicator in atomic and molecular gas
• A WENO algorithm for radiative transfer with resonant scattering: the time scale of the Wouthuysen-Field Coupling
• 21cmFirstCLASS II. Early linear fluctuations of the 21cm signal
• Maximum amplitude of the high-redshift 21-cm absorption feature
• The EDGES measurement disfavors an excess radio background during the cosmic dawn
• Mapping discrete galaxies at cosmic dawn with 21-centimeter observations
• Astrophysical information from the Rayleigh-Jeans Tail of the CMB
• Effects of feedback-free starburst galaxies on the 21-cm signal and reionization history
• Bounds on sterile neutrino lifetime and mixing angle with active neutrinos by global 21 cm signal
• Intergalactic heating by Lyman-alpha photons including hyperfine structure corrections
• The impact of Lyman-$\alpha$ emission line heating and cooling on the cosmic dawn 21-cm signal
• Galactic wind X-ray heating of the intergalactic medium during the Epoch of Reionization
• Requirements for Cosmological 21-cm Masers
• Let there be Light: the Emergence of Structure out of the Dark Ages in the Early Universe
• The ultimate frontier of 21cm cosmology
• Joint 21-cm and CMB Forecasts for Constraining Self-Interacting Massive Neutrinos
• Radiative transfer of Lyman-$\alpha$ photons at cosmic dawn with realistic gas physics
• Impact of cosmic rays on the global 21-cm signal during cosmic dawn
• Analytic Formulation of 21 cm Signal from Cosmic Dawn: Ly$\alpha$ Fluctuations
• Constraints on freeze-in dark matter from Lyman-$\alpha$ forest and 21-cm signal : single-field models
• Lyman-alpha Heating of Inhomogeneous High-redshift Intergalactic Medium
• 21-cm Constraints on Dark Matter Annihilation after an Early Matter-Dominated Era
• Analyzing the 21-cm signal brightness temperature in the Universe with inhomogeneities
• Probing self-interacting ultrahigh-energy neutrinos with the cosmic 21-cm signal
• Global signal in the redshifted hydrogen 21-cm line from the Dark Ages and Cosmic Dawn: Dependence on the nature of dark matter and modeling of first light
• Lyman-α polarization from cosmological ionization fronts: I. Radiative transfer simulations
• On Measuring the 21 cm Global Spectrum of the Cosmic Dawn with an Interferometer Array
• The First Stars May Shed Light on Dark Matter
• Catching p via s wave with indirect detection
• On the Detectability of the Hydrogen 3-cm Fine Structure Line from the EoR
• Probing Non-Minimal Dark Sectors via the 21 cm Line at Cosmic Dawn
• In Search of Global 21-cm Signal using Artificial Neural Network in light of ARCADE 2
• 21 cm Signal from the Thermal Evolution of Lyman-$\alpha$ during Cosmic Dawn
• Sensitivity toward dark matter annihilation imprints on 21-cm signal with SKA-Low: A convolutional neural network approach
• Constraining the Hubble parameter with the 21 cm brightness temperature signal in a universe with inhomogeneities
• Infra-red emission line tomography of the intergalactic medium during the Epoch of Reionization
• Astrophysical uncertainties challenge 21-cm forecasts: A primordial black hole case study
• What can we learn about Reionization astrophysical parameters using Gaussian Process Regression?
• The Anomalous 21-cm Absorption at High Redshifts
• Luminosity Bias (II): The Cosmic Web of the First Stars
• Radiative Transfer Simulations of Ly$\alpha$ Intensity Mapping During Cosmic Reionization Including Sources from Galaxies and the Intergalactic Medium
• Absorption in the 21 cm Hydrogen Line at $z>10$ as a Sensitive Tool for the Construction of a Cosmological Model on Small Scales
• Thermal Evolution of the IGM due to Lyman-α photons during the Cosmic Dawn
• The haloes that reionized the Universe
• 21 cm Cosmology Sensitivity to Small-Scale Structure: Warm vs Neutrino-Interacting Dark Matter
• Cosmological bounds on dark matter annihilation using dark ages 21-cm signal
• Bounds on Dark Matter Annihilation Cross-sections from Inert Doublet Model in the context of 21 cm Cosmology of Dark Ages
• Simulation based inference of the ionization history from the 2D 21 cm power spectrum