Semi-Analytic Models for Dark Matter Halos

TL;DR

This paper develops semi-analytic models for dark matter halos, deriving density profiles, phase-space distributions, and energy distributions for various profiles, with applications to dark matter detection and cosmological halo formation.

Contribution

It introduces semi-analytic models with explicit formulas for density and phase-space distributions of dark matter halos, covering different inner cusp slopes and anisotropies.

Findings

Derived phase-space distribution functions for multiple halo profiles.

Provided analytic fitting formulas for practical applications.

Discussed implications for dark matter detection and halo formation studies.

Abstract

Various analytic expressions have been proposed for the density profile of dark matter halos. We consider six of these expressions for which the density profile has a power-law fall-off rho proportional to r^{-3} at large radii and a power-law cusp rho proportional to r^{-gamma} (gamma=0, 1/2, 1, 3/2) at small radii. The phase-space distribution function for these models is calculated assuming spherical symmetry and either an isotropic velocity dispersion tensor or an anisotropic dispersion tensor of the type proposed by Osipkov and Merritt. The differential energy distribution for these models is also derived. Several applications are discussed including the analysis of dark matter search experiments and the study of halo formation in a cosmological setting. Analytic fitting formulae for some of the models are provided.