Redshift space distortions of the {\rm HI} 21-cm intensity mapping signal due to the internal motions within galaxies

Abstract

The {\rm HI} 21-cm intensity mapping signal experiences redshift space distortions due to the motion of the galaxies which contain the {\rm HI} as well as the motions of the {\rm HI} gas within the galaxies. A detailed modelling is essential if this signal is to be used for precision cosmology. Considering dark matter only simulations where the {\rm HI} is assumed to reside in galaxies which are associated with haloes, in this work we introduce a technique to incorporate the {\rm HI} motions within the galaxies. This is achieved through a line profile which accounts for both the rotational and random (thermal and turbulent) motions of the {\rm HI} within galaxies. The functional form of the double horned line profiles used here is motivated by observations of $z=0$ spiral galaxies. Analyzing the simulated 21-cm power spectrum over the redshift range $1\le z\le 6$ we find that the {\rm HI} motions within galaxies makes a significant contribution that is manifested as an enhancement in the Finger of God (FoG) effect which can be modelled reasonably well through a Lorentzian damping profile with a single free parameter ${\sigma }_p$. The value of ${\sigma }_p$ is significantly enhanced if motions within the galaxies are included. This is particularly important at $z>3$ where ${\sigma }_p$ is dominated by the internal motions and a measurement of the FoG effect here could provide a handle on the line profiles of high redshift galaxies.

arXiv comment14 Pages, 8 Figures, accepted for publication in MNRAS main journal

References in corpus (106)

• Planck 2015 results. XIII. Cosmological parameters
• Profiles of dark haloes: evolution, scatter, and environment
• Simulating Galaxy Formation with the IllustrisTNG Model
• Constraining the Evolution of the Ionizing Background and the Epoch of Reionization with z ~ 6 Quasars II: A Sample of 19 Quasars
• THINGS: The HI Nearby Galaxy Survey
• Simulating galaxy formation with black hole driven thermal and kinetic feedback
• A model for cosmological simulations of galaxy formation physics
• Evidence for Reionization at z ~ 6: Detection of a Gunn-Peterson Trough in a z=6.28 Quasar
• Observational constraints on Cosmic Reionization
• Reconstructing the linear power spectrum of cosmological mass fluctuations
• Damped Lyman alpha Systems
• The 1000 Brightest HIPASS Galaxies: HI Properties
• Supermassive black holes and their feedback effects in the IllustrisTNG simulation
• The Baryonic Tully-Fisher Relation of Gas Rich Galaxies as a Test of LCDM and MOND
• Fingers of God
• The Atlas3D project -- XIII. Mass and morphology of HI in early-type galaxies as a function of environment
• The SDSS Damped Lya Survey: Data Release 3
• Measuring the cosmological constant with redshift surveys
• Baryon Acoustic Oscillation Intensity Mapping as a Test of Dark Energy
• Measurement of 21 cm brightness fluctuations at z ~ 0.8 in cross-correlation
• Late-time cosmology with 21cm intensity mapping experiments
• Linear Redshift Distortions: A Review
• Determination of z~0.8 neutral hydrogen fluctuations using the 21 cm intensity mapping auto-correlation
• Surveys for z > 3 Damped Lyman-alpha Absorption Systems
• Damped Lyman Alpha Systems in Galaxy Formation Simulations
• FIGGS: Faint Irregular Galaxies GMRT Survey - Overview, observations and first results
• The CMBR fluctuations from HI perturbations prior to reionization
• Disk galaxies at Z=0 and at High Redshift: an explanation of the observed evolution of damped Ly-alpha systems
• Ingredients for 21cm intensity mapping
• The Neutral Hydrogen Content of Galaxies in Cosmological Hydrodynamic Simulations
• Possibility of Precise Measurement of the Cosmological Power Spectrum With a Dedicated 21cm Survey After Reionization
• Simulation of the Cosmic Evolution of Atomic and Molecular Hydrogen in Galaxies
• The ESO UVES Advanced Data Products Quasar Sample - II. Cosmological Evolution of the Neutral Gas Mass Density
• The HI content of star-forming galaxies at z = 0.24
• The Compression of Dark Matter Halos by Baryonic Infall
• Fourier Analysis of Redshift Space Distortions and the Determination of Omega
• Line-Intensity Mapping: 2017 Status Report
• Baryonic Acoustic Oscillations in 21cm Emission: A Probe of Dark Energy out to High Redshifts
• The large-scale cross-correlation of Damped Lyman Alpha Systems with the Lyman Alpha Forest: First Measurements from BOSS
• Detection of HI in distant galaxies using spectral stacking
• Optical-to-virial velocity ratios of local disk galaxies from combined kinematics and galaxy-galaxy lensing
• A First Attempt to Calibrate the Baryonic Tully-Fisher Relation with Gas Dominated Galaxies
• Galaxy Simulation with Dust Formation and Destruction
• Damped Lyman-alpha absorbers as a probe of stellar feedback
• Using HI to probe large scale structures at z ~ 3
• A ground-based 21cm Baryon acoustic oscillation survey
• HI as a Probe of the Large Scale Structure in the Post-Reionization Universe
• HI Fluctuations at Large Redshifts: I--Visibility correlation
• Redshift space bias and beta from the halo model
• The Nature of Damped Lyman Alpha Systems and Their Hosts in the Standard Cold Dark Matter Universe
• The redshift space power spectrum in the halo model
• Neutral atomic hydrogen (HI) gas evolution in field galaxies at z ~ 0.1 and 0.2
• A Virtual Sky with Extragalactic HI and CO Lines for the SKA and ALMA
• Reproducing the Kinematics of Damped Lyman-alpha Systems
• Fluctuations in 21cm Emission After Reionization
• The HI gas content of galaxies around Abell 370, a galaxy cluster at z = 0.37
• A halo model for cosmological neutral hydrogen: abundances and clustering
• Damped Lyman Alpha Systems vs. Cold + Hot Dark Matter
• The busy function: a new analytic function for describing the integrated 21-cm spectral profile of galaxies
• On the spatial distribution of neutral hydrogen in the Universe: bias and shot-noise of the HI Power Spectrum
• Modeling the neutral hydrogen distribution in the post-reionization Universe: intensity mapping
• Damped Lyman alpha absorber and the faint end of the galaxy luminosity function at high redshift
• High-redshift post-reionization cosmology with 21cm intensity mapping
• Improved foreground removal in GMRT 610 MHz observations towards redshifted 21-cm tomography
• Survey for Galaxies Associated with z~3 Damped Lyman alpha Systems II: Galaxy-Absorber Correlation Functions
• The 21cm Power Spectrum After Reionization
• HI velocity dispersion in NGC 1058
• Constraining a halo model for cosmological neutral hydrogen
• The gas mass of star-forming galaxies at $z\approx 1.3$
• Modelling the post-reionization neutral Hydrogen (\HI) bias
• GMRT observation towards detecting the Post-reionization 21-cm signal
• Estimation of Cosmological Parameters from HI Observations of Post-reionization Epoch
• Measuring our universe from galaxy redshift surveys
• Modeling The Large Scale Bias of Neutral Hydrogen
• Constraints on Models of Galaxy Formation from the Evolution of Damped Ly$\alpha$ Absorption Systems
• The bias of DLAs at z ~ 2.3: contraining stellar feedback in shallow potential wells
• Neutral hydrogen in galaxy clusters: impact of AGN feedback and implications for intensity mapping
• Constraining large scale HI bias using redshifted 21-cm signal from the post-reionization epoch
• HI Fluctuations at Large Redshifts: III - Simulating the Signal Expected at GMRT
• The HI content of dark matter halos at $z\approx 0$ from ALFALFA
• Intensity mapping with neutral hydrogen and the Hidden Valley simulations
• Constraints on the evolution of the relationship between HI mass and halo mass in the last 12 Gyr
• Near term measurements with 21 cm intensity mapping: neutral hydrogen fraction and BAO at z<2
• The cross-correlation between 21cm intensity mapping maps and the Lyman-alpha forest in the post-reionization era
• Estimating beta from redshift-space distortions in the 2dF galaxy survey
• Measuring the growth of structure with intensity mapping surveys
• HI Fluctuations at Large Redshifts: II - the Signal Expected for GMRT
• Probing the bispectrum at high redshifts using 21 cm HI observations
• Detecting neutral hydrogen in emission at redshift z ~ 1
• The spatial distribution of neutral hydrogen as traced by low HI mass galaxies
• Modelling redshift-space distortion in the post-reionization $\mathrm{HI}$ 21-cm power spectrum
• Damped Lyman Alpha Systems at High Redshift and Models of Protogalactic Disks
• Impact of astrophysics on cosmology forecasts for 21 cm surveys
• Nonlinear modulation of the HI power spectrum on ultra-large scales. I
• A scale dependent bias on linear scales: the case for HI intensity mapping at z=1
• Redshift Space Distortion of 21cm line at 1<z<5 with Cosmological Hydrodynamic Simulations
• A Simple Model for Global HI Profiles of Galaxies
• Imprint of non-linear effects on HI intensity mapping on large scales
• CMBR Weak Lensing and HI 21-cm Cross-correlation Angular Power Spectrum
• Predictions for BAO distance estimates from the cross-correlation of the Lyman-alpha forest and redshifted 21-cm emission
• Fisher Matrix Based Predictions for Measuring the z = 3.35 Binned 21-cm Power Spectrum using the Ooty Wide Field Array (OWFA)
• The CMBR ISW and HI 21-cm Cross-correlation Angular Power Spectrum
• Predictions for measuring the cross power spectrum of the HI 21-cm signal and the Lyman-$\alpha$ forest using OWFA
• Probing primordial non-Gaussianity: The 3D Bispectrum of Ly-alpha forest and the redshifted 21-cm signal from the post reionization epoch
• Simulating the z = 3.35 HI 21-cm visibility signal for the Ooty Wide Field Array(OWFA)
• Visibility-based Power Spectrum Estimation for Low-Frequency Radio Interferometric Observations

Cited by in corpus (13)

• Detection of Cosmological 21 cm Emission with the Canadian Hydrogen Intensity Mapping Experiment
• Multi-tracer intensity mapping: Cross-correlations, Line noise & Decorrelation
• Detecting the relativistic bispectrum in 21cm intensity maps
• Multipole expansion for HI intensity mapping experiments: simulations and modelling
• A model of spectral line broadening in signal forecasts for line-intensity mapping experiments
• The BINGO Project VI: HI Halo Occupation Distribution and Mock Building
• Modelling the post-reionization neutral hydrogen ($\mathrm{HI}$) 21-cm bispectrum
• Measuring the cosmic expansion rate using 21-cm velocity acoustic oscillations
• Interferometric HI intensity mapping: perturbation theory predictions and foreground removal effects
• Quantifying the redshift space distortion of the bispectrum III : Detection prospects of the multipole moments
• The parameter-free Finger-Of-God model and its application to 21cm intensity mapping
• Using strong gravitational lensing to probe the post reionization \HI power spectrum
• Tracing Signatures of Modified Gravity in Redshift-Space Galaxy Bispectrum Multipoles: Prospects for Euclid