Redshifted 21-cm Bispectrum I: Impact of the Redshift Space Distortions on the Signal from the Epoch of Reionization

Abstract

The bispectrum can quantify the non-Gussianity present in the redshifted 21-cm signal produced by the neutral hydrogen (HI) during the epoch of reionization (EoR). Motivated by this, we perform a comprehensive study of the EoR 21-cm bispectrum using simulated signals. Given a model of reionization, we demonstrate the behaviour of the bispectrum for all unique triangles in $k$ space. For ease of identification of the unique triangles, we parametrize the $k$-triangle space with two parameters, namely the ratio of the two arms of the triangle ($n=k_2/k_1$) and the cosine of the angle between them ($\cos \theta$). Furthermore, for the first time, we quantify the impact of the redshift space distortions (RSD) on the spherically averaged EoR 21-cm bispectrum in the entire unique triangle space. We find that the real space signal bispectra for small and intermediate $k_1$-triangles ($k_1\le 0.6\mathrm{Mp}{\mathrm{c}}^{-1}$) is negative in most of the unique triangle space. It takes a positive sign for squeezed, stretched and linear $k_1$-triangles, specifically for large $k_1$ values ($k_1\ge 0.6\mathrm{Mp}{\mathrm{c}}^{-1}$). The RSD affects both the sign and magnitude of the bispectra significantly. It changes (increases/decreases) the magnitude of the bispectra by $50-100\%$ without changing its sign (mostly) during the entire period of the EoR for small and intermediate $k_1$-triangles. For larger $k_1$-triangles, RSD affects the magnitude by $100-200\%$ and also flips the sign from negative to positive. We conclude that it is important to take into account the impact of RSD for a correct interpretation of the EoR 21-cm bispectra.

arXiv comment18 pages, 11 figures. Accepted for publication in the MNRAS. Replaced to match the accepted version

References in corpus (87)

• Seven-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• Planck 2013 results. XVI. Cosmological parameters
• Cosmology at Low Frequencies: The 21 cm Transition and the High-Redshift Universe
• 21-cm cosmology
• Evidence for Reionization at z ~ 6: Detection of a Gunn-Peterson Trough in a z=6.28 Quasar
• Cosmic Reionization and Early Star-Forming Galaxies: A Joint Analysis of New Constraints from Planck and Hubble Space Telescope
• A Survey of z>5.7 Quasars in the Sloan Digital Sky Survey II: Discovery of Three Additional Quasars at z>6
• Statistics of 207 Lya Emitters at a Redshift Near 7: Constraints on Reionization and Galaxy Formation Models
• The Growth of HII Regions During Reionization
• Cosmological Parameter Estimation Using 21 cm Radiation from the Epoch of Reionization
• Efficient Simulations of Early Structure Formation and Reionization
• Reionization after Planck: The Derived Growth of the Cosmic Ionizing Emissivity now matches the Growth of the Galaxy UV Luminosity Density
• What Next-Generation 21 cm Power Spectrum Measurements Can Teach Us About the Epoch of Reionization
• A simulation calibrated limit on the HI power spectrum from the GMRT Epoch of Reionization experiment
• Improved upper limits on the 21-cm signal power spectrum of neutral hydrogen at $\mathbf{z}\approx 9.1$ from LOFAR
• Upper limits on the 21-cm Epoch of Reionization power spectrum from one night with LOFAR
• Probing the Ionization State of the Universe at z>6
• Foreground simulations for the LOFAR - Epoch of Reionization Experiment
• A Method for Separating the Physics from the Astrophysics of High-Redshift 21cm Fluctuations
• 21CMMC: an MCMC analysis tool enabling astrophysical parameter studies of the cosmic 21 cm signal
• Planck intermediate results. XLVII. Planck constraints on reionization history
• Deep multi-redshift limits on Epoch of Reionisation 21cm Power Spectra from Four Seasons of Murchison Widefield Array Observations
• The CMBR fluctuations from HI perturbations prior to reionization
• The Evolution of Lyman Limit Absorption Systems to Redshift Six
• Radio Foregrounds for the 21cm Tomography of the Neutral Intergalactic Medium at High Redshifts
• Evolution of the 21 cm signal throughout cosmic history
• Inside-out or Outside-in: The topology of reionization in the photon-starved regime suggested by Lyman-alpha forest data
• The Galaxy Luminosity Function during the Reionization Epoch
• Detecting the Rise and Fall of 21 cm Fluctuations with the Murchison Widefield Array
• On using visibility correlations to probe the HI distribution from the dark ages to the present epoch I: Formalism and the expected signal
• Cosmic reionization after Planck
• A simplified, lossless re-analysis of PAPER-64
• Improving the Epoch of Reionization Power Spectrum Results from Murchison Widefield Array Season 1 Observations
• Power Spectrum Sensitivity and the Design of Epoch of Reionization Observatories
• Redshift Space Distortion of the 21cm Background from the Epoch of Reionization I: Methodology Re-examined
• Lyman-alpha emitters gone missing: evidence for late reionization?
• Foregrounds for redshifted 21 cm studies of reionization: GMRT 153 MHz observations
• Quantifying the non-Gaussianity in the EoR 21-cm signal through bispectrum
• 21 cm signal from cosmic dawn: Imprints of spin temperature fluctuations and peculiar velocities
• The multi-frequency angular power spectrum of the epoch of reionization 21 cm signal
• Characterizing Foreground for redshifted 21-cm radiation: 150 MHz GMRT observations
• Light cone effect on the reionization 21-cm power spectrum
• Constraining the intergalactic medium at $z\approx$ 9.1 using LOFAR Epoch of Reionization observations
• On the Use of Ly-alpha Emitters as Probes of Reionization
• First Season MWA Phase II EoR Power Spectrum Results at Redshift 7
• On the use of semi-numerical simulations in predicting the 21-cm signal from the epoch of reionization
• Tight Constraints on the Excess Radio Background at $z=9.1$ from LOFAR
• Probing reionization with LOFAR using 21-cm redshift space distortions
• A New Constraint on Reionization from Evolution of the Ly$\alpha$ Luminosity Function at $z\sim 6-7$ Probed by a Deep Census of $z=7.0$ Ly$\alpha$ Emitter Candidates to 0.3 $L^{\ast }$
• Probing non-Gaussian features in the HI distribution at the epoch of reionization
• Higher Order Contributions to the 21 cm Power Spectrum
• Light cone effect on the reionization 21-cm signal II: Evolution, anisotropies and observational implications
• The 21cm bispectrum as a probe of non-Gaussianities due to X-ray heating
• 21cm-line bispectrum as method to probe Cosmic Dawn and Epoch of Reionization
• Statistics of the epoch of reionization (EoR) 21-cm signal -- II. The evolution of the power spectrum error-covariance
• The 21cm bispectrum during reionization: a tracer of the ionization topology
• The effect of non-Gaussianity on error predictions for the Epoch of Reionization (EoR) 21-cm power spectrum
• Constraining the epoch of reionization with the variance statistic: simulations of the LOFAR case
• Detection and extraction of signals from the epoch of reionization using higher order one-point statistics
• Towards simulating and quantifying the light-cone EoR 21-cm signal
• Distinguishing models of reionization using future radio observations of 21-cm 1-point statistics
• Observations of the Lyman series forest towards the redshift 7.1 quasar ULAS J1120+0641
• Position-dependent power spectra of the 21-cm signal from the epoch of reionization
• Sensitivity for 21cm Bispectrum from Epoch of Reionization
• Implications of WMAP 3 Year Data for the Sources of Reionization
• The impact of spin temperature fluctuations on the 21-cm moments
• The effect of peculiar velocities on the epoch of reionization (EoR) 21-cm signal
• Quantifying the Redshift Space Distortion of the Bispectrum I: Primordial Non-Gaussianity
• Statistics of the epoch of reionization 21-cm signal - I. Power spectrum error-covariance
• Studying 21cm power spectrum with one-point statistics
• Studying the Sources of Cosmic Reionization with 21-cm Fluctuations
• Effects of the sources of reionization on 21-cm redshift-space distortions
• Gridded and direct Epoch of Reionisation bispectrum estimates using the Murchison Widefield Array
• Reconstructing the nature of the first cosmic sources from the anisotropic 21-cm signal
• What will anisotropies in the clustering pattern in redshifted 21 cm maps tell us?
• Probing the bispectrum at high redshifts using 21 cm HI observations
• Predictions for measuring the 21-cm multi-frequency angular power spectrum using SKA-Low
• Exploring the Cosmic Reionization Epoch in Frequency Space: An Improved Approach to Remove the Foreground in 21 cm Tomography
• A method to determine the evolution history of the mean neutral Hydrogen fraction
• Detecting the 21 cm Forest in the 21 cm Power Spectrum
• Quantifying the Redshift Space Distortion of the Bispectrum II: Induced Non-Gaussianity at Second Order Perturbation
• Expected constraints on models of the epoch of reionization with the variance and skewness in redshifted 21cm-line fluctuations
• The bispectrum and 21cm foregrounds during the Epoch of Reionization
• Reionisation & Cosmic Dawn Astrophysics from the Square Kilometre Array: Impact of Observing Strategies
• Impact of dark matter models on the EoR 21-cm signal bispectrum
• High-Redshift Galaxy Surveys and the Reionization of the Universe
• Line of sight anisotropies in the Cosmic Dawn and EoR 21-cm power spectrum

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• Interpreting the HI 21-cm cosmology maps through Largest Cluster Statistics -- I: Impact of the synthetic SKA1-Low observations
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• The Impact of ionization Morphology and X-ray Heating on the Cosmological 21cm Skew Spectrum
• Exploring One-point Statistics in HERA Phase I Data: Effects of Foregrounds and Systematics on Measuring One-Point Statistics
• From ANN to BNN: Inferring Reionization Parameters using Uncertainty-aware Emulators of 21-cm Summaries
• The Effect of Large Optical Depths on the Non-Gaussian 21-cm signal from Cosmic Dawn
• Probing the large-scale structure with 21cm-galaxy cross-bispectrum: Estimates from simulations and forecasts for upcoming cosmological surveys