A semi-analytic model of pairwise velocity distribution between dark matter halos

Abstract

We study the probability distribution function (PDF) of relative velocity between two different dark matter halos (i.e. pairwise velocity) with a set of high-resolution cosmological $N$-body simulations. We investigate the pairwise velocity PDFs over a wide range of halo masses of $10^{12.5-15}{h}^{-1}{M}_{\odot }$ and redshifts of $0<z<1$. At a given set of masses, redshift and the separation length between two halos, our model requires three parameters to set the pairwise velocity PDF, whereas previous non-Gaussian models in the literature assume four or more free parameters. At the length scales of $r=5-40[h^{-1}\mathrm{Mpc}]$, our model predicts the mean and dispersion of the pairwise velocity for dark matter halos with their masses of $10^{12.5-13.5}[h^{-1}{M}_{\odot }]$ at $0.3<z<1$ with a 5%-level precision, while the model precision reaches a 20% level (mostly a 10% level) for other masses and redshifts explored in the simulations. We demonstrate that our model of the pairwise velocity PDF provides an accurate mapping of the two-point clustering of massive-galaxy-sized halos at the scales of $O(10)h^{-1}\mathrm{Mpc}$ between redshift and real space for a given real-space correlation function. For a mass-limited halo sample with their masses greater than $10^{13.5}{h}^{-1}{M}_{\odot }$ at $z=0.55$, our model can explain the monopole and quadropole moments of the redshift-space two-point correlations with a precision better than 5% at the scales of $5-40$ and $10-30h^{-1}\mathrm{Mpc}$, respectively. Our model of the pairwise velocity PDF will give a detailed explanation of statistics of massive galaxies at the intermediate scales in redshift surveys, including the non-linear redshift-space distortion effect in two-point correlation functions and the measurements of the kinematic Sunyaev-Zel'dovich effect.

arXiv comment29 pages, 16 figures, 2 tables, Accepted for publication in ApJ

References in corpus (65)

• Planck 2015 results. XIII. Cosmological parameters
• The Structure of Cold Dark Matter Halos
• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• Efficient Computation of CMB anisotropies in closed FRW models
• Baryonic Features in the Matter Transfer Function
• Halo Models of Large Scale Structure
• Toward a halo mass function for precision cosmology: the limits of universality
• The Rockstar Phase-Space Temporal Halo Finder and the Velocity Offsets of Cluster Cores
• Observational Probes of Cosmic Acceleration
• Revising the Halofit Model for the Nonlinear Matter Power Spectrum
• The Large Scale Bias of Dark Matter Halos: Numerical Calibration and Model Tests
• The Luminosity and Color Dependence of the Galaxy Correlation Function
• Large-Scale Galaxy Bias
• Galaxy Clustering in the Completed SDSS Redshift Survey: The Dependence on Color and Luminosity
• Transients from Initial Conditions in Cosmological Simulations
• Halo concentrations in the standard LCDM cosmology
• Galaxy Evolution from Halo Occupation Distribution Modeling of DEEP2 and SDSS Galaxy Clustering
• Redshift-Space Distortions, Pairwise Velocities and Nonlinearities
• New constraints on the evolution of the stellar-to-dark matter connection: a combined analysis of galaxy-galaxy lensing, clustering, and stellar mass functions from z=0.2 to z=1
• On the Mass-to-Light Ratio of Large Scale Structure
• A universal model for halo concentrations
• Halo assembly bias and its effects on galaxy clustering
• The clustering of massive galaxies at z~0.5 from the first semester of BOSS data
• Evidence of Galaxy Cluster Motions with the Kinematic Sunyaev-Zel'dovich Effect
• Observational Tests of Modified Gravity
• Cosmological Constraints from a Combination of Galaxy Clustering and Lensing -- I. Theoretical Framework
• Halo Occupation Distribution Modeling of Clustering of Luminous Red Galaxies
• A 2.5% measurement of the growth rate from small-scale redshift space clustering of SDSS-III CMASS galaxies
• Dark Quest. I. Fast and Accurate Emulation of Halo Clustering Statistics and Its Application to Galaxy Clustering
• Galaxy Assembly Bias: A Significant Source of Systematic Error in the Galaxy-Halo Relationship
• The Coyote Universe III: Simulation Suite and Precision Emulator for the Nonlinear Matter Power Spectrum
• Halo Model at Its Best: Constraints on Conditional Luminosity Functions from Measured Galaxy Statistics
• Probability Distribution Function of Cosmological Density Fluctuations from Gaussian Initial Condition: Comparison of One- and Two-point Log-normal Model Predictions with N-body Simulations
• The Weak Lensing Signal and the Clustering of BOSS Galaxies II: Astrophysical and Cosmological Constraints
• The Aemulus Project III: Emulation of the Galaxy Correlation Function
• Evolution of One-Point Distributions from Gaussian Initial Fluctuations
• The Aemulus Project II: Emulating the Halo Mass Function
• Cosmic Calibration: Constraints from the Matter Power Spectrum and the Cosmic Microwave Background
• GreeM : Massively Parallel TreePM Code for Large Cosmological N-body Simulations
• Velocity Bias from the Small Scale Clustering of SDSS-III BOSS Galaxies
• Redshift-Space Distortions with the Halo Occupation Distribution II: Analytic Model
• Limitations to the "basic'' HOD model and beyond
• Cosmic Emulation: Fast Predictions for the Galaxy Power Spectrum
• An excursion set model of the cosmic web: The abundance of sheets, filaments and halos
• Detection of the pairwise kinematic Sunyaev-Zel'dovich effect with BOSS DR11 and the Atacama Cosmology Telescope
• Constraining the LRG Halo Occupation Distribution using Counts-in-Cylinders
• A clear and measurable signature of modified gravity in the galaxy velocity field
• An Extended Excursion Set Approach to Structure Formation in Chameleon Models
• The Morphology of Galaxies in the Baryon Oscillation Spectroscopic Survey
• The ${\nu }^2$GC Simulations : Quantifying the Dark Side of the Universe in the Planck Cosmology
• Testing Gravity with the Stacked Phase Space around Galaxy Clusters
• Galaxy Infall Kinematics as a Test of Modified Gravity
• The Redshift-Space Cluster-Galaxy Cross-Correlation Function: I. Modeling Galaxy Infall onto Millennium Simulation Clusters and SDSS Groups
• Accurate and Efficient Halo-based Galaxy Clustering Modelling with Simulations
• The Correlation Between Halo Mass and Stellar Mass for the Most Massive Galaxies in the Universe
• Cosmic Emulation: The Concentration-Mass Relation for wCDM Universes
• Improving the modelling of redshift-space distortions - II. A pairwise velocity model covering large and small scales
• Dependence of Halo Bias and Kinematics on Assembly Variables
• Clustering of dark matter halos on the light-cone: scale-, time- and mass-dependence of the halo biasing in the Hubble volume simulations
• Towards a non-Gaussian model of redshift space distortions
• On the streaming model for redshift-space distortions
• A direct measure of free electron gas via the Kinematic Sunyaev-Zel'dovich effect in Fourier-space analysis
• New fitting formula for cosmic non-linear density distribution
• The Effect of Assembly Bias on Redshift Space Distortions
• Ellipsoidal collapse and the redshift space probability distribution function of dark matter

Cited by in corpus (6)

• Redshift-space distortions with split densities
• Stacked phase-space density of galaxies around massive clusters: Comparison of dynamical and lensing masses
• FLAMINGO: Galaxy formation and feedback effects on the gas density and velocity fields
• The RSD Sorting Hat: Unmixing Radial Scales in Projection
• Galaxy Velocity Bias in Cosmological Simulations: Towards Percent-level Calibration
• Information content in mean pairwise velocity and mean relative velocity between pairs in a triplet