A method to determine the evolution history of the mean neutral Hydrogen fraction

Abstract

The light-cone (LC) effect imprints the cosmological evolution of the redshifted 21-cm signal $T_{\mathrm{b}}(\hat{\mathbf{n}},\nu )$ along the frequency axis which is the line of sight (LoS) direction of an observer. The effect is particularly pronounced during the Epoch of Reionization (EoR) when the mean hydrogen neutral fraction ${\bar{x}}_{\mathrm{HI}}(\nu )$ falls rapidly as the universe evolves. The multi-frequency angular power spectrum (MAPS) ${\mathcal{C}}_{\ell }({\nu }_1,{\nu }_2)$ quantifies the entire second-order statistics of $T_{\mathrm{b}}(\hat{\mathbf{n}},\nu )$ considering both the systematic variation along $\nu$ due to the cosmological evolution and also the statistically homogeneous and isotropic fluctuations along all the three spatial directions encoded in $\hat{\mathbf{n}}$ and $\nu$. Here we propose a simple model where the systematic frequency $({\nu }_1,{\nu }_2)$ dependence of ${\mathcal{C}}_{\ell }({\nu }_1,{\nu }_2)$ arises entirely due to the evolution of ${\bar{x}}_{\mathrm{HI}}(\nu )$. This provides a new method to observationally determine the reionization history. Considering a LC simulation of the EoR 21-cm signal, we use the diagonal elements ${\nu }_1={\nu }_2$ of ${\mathcal{C}}_{\ell }({\nu }_1,{\nu }_2)$ to validate our model. We demonstrate that it is possible to recover the reionization history across the entire observational bandwidth provided we have the value ${\bar{x}}_{\mathrm{HI}}$ at a single frequency as an external input.

arXiv commentPublished in Monthly Notices of the Royal Astronomical Society (MNRAS) Letters. Available at https://doi.org/10.1093/mnrasl/sly226

References in corpus (36)

• Planck 2013 results. XVI. Cosmological parameters
• LOFAR: The LOw-Frequency ARray
• The Murchison Widefield Array: the Square Kilometre Array Precursor at low radio frequencies
• Hydrogen Epoch of Reionization Array (HERA)
• Simulating Cosmic Reionization at Large Scales I: the Geometry of Reionization
• Reionization and the Cosmic Dawn with the Square Kilometre Array
• A simulation calibrated limit on the HI power spectrum from the GMRT Epoch of Reionization experiment
• Science with the Murchison Widefield Array
• New Limits on 21cm EoR From PAPER-32 Consistent with an X-Ray Heated IGM at z=7.7
• PAPER-64 Constraints on Reionization: The 21cm Power Spectrum at z=8.4
• The CMBR fluctuations from HI perturbations prior to reionization
• Statistical Probes of Reionization With 21 cm Tomography
• Overcoming real-world obstacles in 21 cm power spectrum estimation: A method demonstration and results from early Murchison Widefield Array data
• Inside-out or Outside-in: The topology of reionization in the photon-starved regime suggested by Lyman-alpha forest data
• On using visibility correlations to probe the HI distribution from the dark ages to the present epoch I: Formalism and the expected signal
• Initial deep LOFAR observations of Epoch of Reionization windows: I. The North Celestial Pole
• Redshift Space Distortion of the 21cm Background from the Epoch of Reionization I: Methodology Re-examined
• Quantifying the non-Gaussianity in the EoR 21-cm signal through bispectrum
• The multi-frequency angular power spectrum of the epoch of reionization 21 cm signal
• Light cone effect on the reionization 21-cm power spectrum
• Multi-redshift limits on the 21cm power spectrum from PAPER
• Probing reionization with LOFAR using 21-cm redshift space distortions
• Probing non-Gaussian features in the HI distribution at the epoch of reionization
• Light cone effect on the reionization 21-cm signal II: Evolution, anisotropies and observational implications
• Statistics of the epoch of reionization (EoR) 21-cm signal -- II. The evolution of the power spectrum error-covariance
• The effect of non-Gaussianity on error predictions for the Epoch of Reionization (EoR) 21-cm power spectrum
• Towards simulating and quantifying the light-cone EoR 21-cm signal
• Light-cone anisotropy in 21cm fluctuations during the epoch of reionization
• Reionization on Large Scales IV: Predictions for the 21 cm signal incorporating the light cone effect
• The effect of peculiar velocities on the epoch of reionization (EoR) 21-cm signal
• Statistics of the epoch of reionization 21-cm signal - I. Power spectrum error-covariance
• Cosmic Reionization On Computers. Properties of the Post-reionization IGM
• Light cone anisotropy in 21 cm signal from the epoch of reionization
• Effects of the sources of reionization on 21-cm redshift-space distortions
• Constraining Quasar and IGM Properties Through Bubble Detection in Redshifted 21-cm Maps
• Exploring the evolution of Reionisation using a wavelet transform and the light cone effect

Cited by in corpus (22)

• Redshifted 21-cm Bispectrum I: Impact of the Redshift Space Distortions on the Signal from the Epoch of Reionization
• Detailed study of ELAIS N1 field with the uGMRT -- II. Source Properties and Spectral Variation Of Foreground Power Spectrum from 300-500 MHz Observations
• Redshifted 21-cm bispectrum II: Impact of the spin temperature fluctuations and redshift space distortions on the signal from the Cosmic Dawn
• The impact of non-Gaussianity on the error covariance for observations of the Epoch of Reionization 21-cm power spectrum
• Predictions for measuring the 21-cm multi-frequency angular power spectrum using SKA-Low
• Improved supervised learning methods for EoR parameters reconstruction
• The Epoch of Reionization 21-cm Bispectrum: The impact of light-cone effects and detectability
• The impact of non-Gaussianity on the Epoch of Reionization parameter forecast using 21-cm power spectrum measurements
• Probing early universe through redshifted 21-cm signal: Modelling and observational challenges
• Bubble mapping with the Square Kilometer Array -- I. Detecting galaxies with Euclid, JWST, WFIRST and ELT within ionized bubbles in the intergalactic medium at z>6
• Towards 21-cm Intensity Mapping at $z=2.28$ with uGMRT using the Tapered Gridded Estimator I: Foreground Avoidance
• The multi-frequency angular power spectrum in parameter studies of the cosmic 21-cm signal
• Constraining low redshift [CII] Emission by Cross-Correlating FIRAS and BOSS Data
• Towards $21$-cm intensity mapping at $z=2.28$ with uGMRT using the tapered gridded estimator III: Foreground removal
• Distinguishing reionization models using the largest cluster statistics of the 21-cm maps
• Multi-frequency angular power spectrum of the 21~cm signal from the Epoch of Reionisation using the Murchison Widefield Array
• Towards $21$-cm intensity mapping at $z=2.28$ with uGMRT using the tapered gridded estimator II: Cross-polarization power spectrum
• Interpreting the HI 21-cm cosmology maps through Largest Cluster Statistics -- I: Impact of the synthetic SKA1-Low observations
• Studying the Multi-frequency Angular Power Spectrum of the Cosmic Dawn 21-cm Signal
• Probing the Epoch of Reionization using synergies of line intensity mapping
• The Evolving Power Spectrum for the light cone Epoch of Reionization (EoR) 21-cm signal
• Quantifying and mitigating the effect of snapshot interval in light-cone Epoch of Reionization 21-cm simulations