Modeling Pairwise Peculiar Velocity Distribution Function of Dark Matter from Halo Density Profiles

Abstract

We derive the pairwise peculiar velocity distribution function of dark matter particles applying the dark matter halo approach. Unlike the previous work, we do not assume a Gaussian velocity distribution function of dark matter in a single halo, but compute it self-consistently with the assumed density profile for dark matter halo. The resulting distribution function is well approximated by an exponential distribution which is consistent with the previous observational, numerical and theoretical results. We also compute the pairwise peculiar velocity dispersion for different density profiles, and provide a practical fitting formula. We apply an empirical biasing scheme into our model and present prediction for pairwise peculiar velocity dispersion of {\it galaxies}, and reproduce the previous results of simulations using our semi-analytical method.

16 pages, 9 figures, accepted for publication in PASJ (2002)

References in corpus (2)

• Spatial correlation functions and the pairwise peculiar velocity dispersion of galaxies in the PSCz survey: implications for the galaxy biasing in cold dark matter models
• Probing the Core Structure of Dark Halos with Tangential and Radial Arc Statistics

Cited by in corpus (5)

• An analytic model for the bispectrum of galaxies in redshift space
• Modeling peculiar velocities of dark matter halos
• Spatial and Dynamical Biases in Velocity Statistics of Galaxies
• The pairwise velocity probability density function in models with local primordial non-Gaussianity
• Turning dispersion into signal: density-split analyses of pairwise velocities