Related papers: Might we eventually understand the origin of the d…
One can solve the Jeans equation analytically for equilibrated dark matter structures, once given two pieces of input from numerical simulations. These inputs are 1) a connection between phase-space density and radius, and 2) a connection…
One can solve the Jeans equation analytically for equilibrated dark matter structures, once given two pieces of input from numerical simulations. These inputs are 1) a connection between phase-space density and radius, and 2) a connection…
Cosmological simulations of dark matter structures have shown that the equilibrated dark matter structures have a fairly small angular momentum. It appears from these N-body simulations that the radial profile of the angular momentum has an…
We identify a universal relation between the radial density slope \alpha (r) and the velocity anisotropy \beta (r) for equilibrated structures. This relation holds for a variety of systems, including disk galaxy mergers, spherical…
Dark matter dominates the properties of large cosmological structures such as galaxy clusters, and the mass profiles of the dark matter have been measured for these equilibrated structures for years using X-rays, lensing or galaxy…
We present density profiles, that are solutions of the spherical Jeans equation, derived under the following two assumptions: (i) the coarse grained phase-density follows a power-law of radius, rho/(sigma^3) proportional to r^{-alpha}, and…
We investigate a hypothesis regarding the origin of the scalelength in halos formed in cosmological N-body simulations. This hypothesis can be viewed as an extension of an earlier idea put forth by Merritt and Aguilar. Our findings suggest…
Dark matter particles form halos that contribute the major part of the mass of galaxy clusters. The formation of these cosmological structures have been investigated both observationally and in numerical simulations, which have confirmed…
We make a simple analytical study of radial profiles of dark matter structures, with special attention to the question of the central radial density profile. We let our theoretical assumptions be guided by results from numerical…
All dark matter structures appear to follow a set of universalities, such as phase-space density or velocity anisotropy profiles, however, the origin of these universalities remains a mystery. Any equilibrated dark matter structure can be…
Dark matter haloes in cosmological N-body simulations are affected by processes such as mergers, accretion and the gravitational interaction with baryonic matter. Typically the analysis of dark matter haloes is performed in spherical or…
Dark matter (DM) halos formed in CDM cosmologies seem to be characterized by a power law phase-space density profile. The density of the DM halos is often fitted by the NFW profile but a better fit is provided by the Sersic fitting formula.…
It has long been realized that dark matter halos formed in cosmological N-body simulations are characterized by density profiles rho(r) that, when suitably scaled, have similar shapes. Additionally, combining the density and velocity…
$N$-body simulations have unveiled several apparently universal properties of dark matter halos, including a cusped density profile, a power-law pseudo phase-space density $\rho/\sigma_r^3$, and a linear $\beta-\gamma$ relation between the…
The internal dynamics of a dark matter structure may have the remarkable property that the local temperature in the structure depends on direction. This is parametrized by the velocity anisotropy beta which must be zero for relaxed…
We report statistical results for dark matter (DM) velocity anisotropy, \beta, from a sample of some 6000 cluster-size halos (at redshift zero) identified in a \Lambda CDM hydrodynamical adaptive mesh refinement simulation performed with…
Dark matter density profiles based upon Lambda-CDM cosmology motivate an ansatz velocity distribution function with fewer high velocity particles than the Maxwell-Boltzmann distribution or proposed variants. The high velocity tail of the…
Dark matter haloes from cosmological N-body simulations typically have triaxial shapes and anisotropic velocity distributions. Recently it has been shown that the velocity anisotropy, beta, of cosmological haloes and major merger remnants…
The velocity distribution of dark matter is supposed to be isotropic Maxwell- Boltzmann distribution in most cases, however, its anisotropy is suggested by some simulations. We investigate conditions to give constraints on the anisotropy…
Velocity distribution of dark matter is assumed to be isotropic in most cases, however, anisotropy is suggested in some simulations. Directional direct detection of dark matter is a hopeful way to discriminate the anisotropy of dark matter…