Scaling Relations in the Phase-Space Structure of Dark Matter Haloes

Abstract

We present new scaling relations for the isotropic phase-space distribution functions (DFs) and energy distributions of simulated dark matter haloes. These relations are inspired by those for the singular isothermal sphere with density profile $\rho (r)\propto r^{-2}$, for which the DF satisfies $f(E)\propto r_{\max }^{-2}(E)$ and the energy distribution satisfies $dM/dE\propto r_{\max }(E)$, with $r_{\max }(E)$ being the radius where the gravitational potential equals energy $E$. For the simulated haloes, we find $f(E)\propto r_{\max }^{-2.08}(E)$ and $dM/dE\propto r_{\max }(E)$ across broad energy ranges. In addition, the proportionality coefficients depend on the gravitational constant and the parameters of the best-fit Navarro-Frenk-White density profile. These scaling relations are satisfied by haloes over a wide mass range and provide an efficient method to approximate their DFs and energy distributions. Understanding the origin of these relations may shed more light on halo formation.

arXiv comment10 pages, 5 figures, accepted for publication in MNRAS

References in corpus (34)

• Planck 2015 results. XIII. Cosmological parameters
• A Universal Density Profile from Hierarchical Clustering
• Statistical Properties of X-ray Clusters: Analytic and Numerical Comparisons
• First results from the IllustrisTNG simulations: matter and galaxy clustering
• First results from the IllustrisTNG simulations: the stellar mass content of groups and clusters of galaxies
• First results from the IllustrisTNG simulations: the galaxy color bimodality
• First results from the IllustrisTNG simulations: A tale of two elements -- chemical evolution of magnesium and europium
• First results from the IllustrisTNG simulations: radio haloes and magnetic fields
• Baryon effects on the internal structure of LCDM halos in the EAGLE simulations
• The Growth and Structure of Dark Matter Haloes
• The Phase-Space Density Profiles of Cold Dark Matter Halos
• Resolving Subhaloes' Lives with the Hierarchical Bound-Tracing Algorithm
• Action-based distribution functions for spheroidal galaxy components
• The distribution function of dark matter in massive haloes
• The outer profile of dark matter halos: an analytical approach
• Semi-analytical dark matter halos and the Jeans equation
• The Density and Pseudo-Phase-Space Density Profiles of CDM halos
• Statistical mechanics of collisionless orbits. I. Origin of central cusps in dark-matter halos
• Multi-Dimensional Density Estimation and Phase Space Structure Of Dark Matter Halos
• Distribution function of the dark matter
• Evolution of Phase-Space Density in Dark Matter Halos
• A natural boundary of dark matter haloes revealed around the minimum bias and maximum infall locations
• Phase-Space Structure of Dark-Matter Haloes: Scale-Invariant PDF Driven by Substructure
• Made-to-Measure Dark Matter Haloes, Elliptical Galaxies and Dwarf Galaxies in Action Coordinates
• Theoretical dark matter halo density profile
• Non-universality of dark-matter halos: cusps, cores, and the central potential
• Statistical mechanics of collisionless orbits. II. Structure of halos
• Statistical mechanics of collisionless orbits. III. Comparison with N-body simulations
• Physical evolution of dark matter halo around the depletion boundary
• Accessible Color Sequences for Data Visualization
• Distribution functions for clusters of galaxies from N-body simulations
• The differential energy distribution and the total integrated binding energy of dynamical models
• Testing DARKexp against energy and density distributions of Millennium-II halos
• Power law pseudo phase-space density profiles of dark matter halos: fluke of physics?