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Related papers: The Non-universal Pseudo Phase-Space Density Profi…

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Numerical simulations indicate that cosmological halos display power-law radial profiles of pseudo phase-space density (PPSD), Q=rho/sigma^3, where rho is mass density and sigma velocity dispersion. We test these predictions using the…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-08 A. Biviano , G. A. Mamon

A large body of work based on collisionless cosmological N-body simulations going back over two decades has advanced the idea that collapsed dark matter haloes have simple and approximately universal forms for their mass density and…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-24 Shaun T. Brown , Ian G. McCarthy , Benedikt Diemer , Andreea S. Font , Sam G. Stafford , Simon Pfeifer

We investigate the apparent power-law scaling of the pseudo phase space density (PPSD) in CDM halos. We study fluid collapse, using the close analogy between the gas entropy and the PPSD in the fluid approximation. Our hydrodynamic…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-20 Ethan O. Nadler , S. Peng Oh , Suoqing Ji

We carry out fully 3-dimensional simulations of evolution from self-similar, spherically symmetric linear perturbations of a Cold Dark Matter dominated Einstein-de Sitter universe. As a result of the radial orbit instability, the haloes…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Mark Vogelsberger , Roya Mohayaee , Simon D. M. White

Cosmological N-body simulations indicate that the spherically-averaged density profiles of cold dark matter halos are accurately described by Einasto profiles, where the logarithmic slope is a power-law of adjustable exponent, \gamma…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-18 Aaron D. Ludlow , Julio F. Navarro , Michael Boylan-Kolchin , Volker Springel , Adrian Jenkins , Carlos S. Frenk , Simon D. M. White

We use N-body simulations to investigate the radial dependence of the density and velocity dispersion in cold dark matter (CDM) halos. In particular, we explore how closely Q rho/sigma^3, a surrogate measure of the phase-space density,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Aaron D. Ludlow , Julio F. Navarro , Volker Springel , Mark Vogelsberger , Jie Wang , Simon D. M. White , Adrian Jenkins , Carlos S. Frenk

We investigate the mass profile of LambdaCDM halos using a suite of numerical simulations spanning five decades in halo mass, from dwarf galaxies to rich galaxy clusters. Our analysis confirms the proposal of Navarro, Frenk & White (NFW)…

We investigate the evolution of dark matter halo shapes in cosmological N-body simulations both in scale free Einstein-De Sitter (EdS) and $\Lambda$CDM cosmologies. We compute the axis ratios ($q=b/a,s=c/a$) of well resolved central halos…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-03 Ayan Nanda , Nishikanta Khandai , J. S. Bagla , Swati Gavas

We present a novel perspective on the clustering of dark matter in phase space by defining the particle phase space average density ($P^2SAD$) as a two-dimensional extension of the two-point correlation function averaged within a certain…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-05 Jesus Zavala , Niayesh Afshordi

Using a generalized self-similar secondary infall model, which accounts for tidal torques acting on the halo, we analyze the velocity profiles of halos in order to gain intuition for N-body simulation results. We analytically calculate the…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-23 Phillip Zukin , Edmund Bertschinger

Simulated dark matter profiles are often modelled as a `NFW' density profile rather than a single power law. Recently, attention has turned to the rather rigorous power-law behaviour exhibited by the `pseudo phase-space density' of the dark…

Astrophysics · Physics 2008-11-26 R. N. Henriksen

We investigate the structure of cold dark matter halos using advanced models of spherical collapse and accretion in an expanding Universe. These base on solving time-dependent equations for the moments of the phase-space distribution…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 A. Lapi , A. Cavaliere

This papers explores the self similar solutions of the Vlasov-Poisson system and their relation to the gravitational collapse of dynamically cold systems. Analytic solutions are derived for power law potential in one dimension, and…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-31 C. Alard

We use a set of high-resolution simulations of scale-free Einstein-de Sitter cosmologies to investigate the logarithmic slope of the phase-space density profile $Q(r) = \rho(r)/\sigma^3(r)$ of dark matter (DM) haloes. The initial conditions…

Astrophysics · Physics 2009-11-13 Steffen R. Knollmann , Alexander Knebe , Yehuda Hoffman

We present the first results from the Rhapsody cluster re-simulation project: a sample of 96 "zoom-in" simulations of dark matter halos of 10^14.8 +- 0.05 Msun/h, selected from a 1 (Gpc/h)^3 volume. This simulation suite is the first to…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-11 Hao-Yi Wu , Oliver Hahn , Risa H. Wechsler , Yao-Yuan Mao , Peter S. Behroozi

(Abridged) We study the outer density profiles of dark matter haloes predicted by a generalized secondary infall model and observed in a N-body cosmological simulation of a \Lambda CDM model. We find substantial systematic variations in…

Astrophysics · Physics 2009-10-31 V. Avila-Reese , C. Firmani , A. Klypin , A. V. Kravtsov

It is well established from cosmological simulations that dark matter haloes are not precisely self-similar and an additional parameter, beyond their concentration, is required to accurately describe their spherically-averaged mass density…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-08 Shaun T. Brown , Ian G. McCarthy , Sam G. Stafford , Andreea S. Font

We derive the density profile for collisionless dissipationless dark matter haloes in hierarchical cosmologies making use of the Secondary Infall (SI) model. The novelties are: i) we deal with triaxial virialised objects; ii) their seeds in…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-10 Eduard Salvador-Solé , Jordi Viñas , Alberto Manrique , Sinue Serra

In two previous papers (Salvador-Sol\'e 2012a,b), it was shown that: i) the typical structural and kinematic properties of haloes in (bottom-up) hierarchical cosmologies endowed with random Gaussian density perturbations of dissipationless…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-20 Eduard Salvador-Solé , Sinue Serra , Alberto Manrique

The phase-space structure of primordial dark matter halos is revisited using cosmological simulations with three sine waves and Cold Dark Matter (CDM) initial conditions. The simulations are performed with the tessellation based Vlasov…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-17 Stéphane Colombi
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