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相关论文: On the Apparent Power Law in CDM Halo Pseudo Phase…

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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…

Cosmological N-body simulations have long suggested that the pseudo phase-space density (PPSD), $\rho/\sigma^3$, of cold dark matter haloes follows the universal relation $\rho/\sigma^3 \propto r^{\chi}$, with $\chi \approx -1.875$, as…

宇宙学与河外天体物理 · 物理学 2026-04-15 Bocheng Feng , Ethan O. Nadler , S. Peng Oh , Suoqing Ji

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,…

宇宙学与河外天体物理 · 物理学 2015-05-18 Aaron D. Ludlow , Julio F. Navarro , Volker Springel , Mark Vogelsberger , Jie Wang , Simon D. M. White , Adrian Jenkins , Carlos S. Frenk

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…

天体物理学 · 物理学 2008-11-26 R. N. Henriksen

In this letter we present a measurement of the phase-space density distribution (PSDD) of ultra-cold \Rb atoms performing 1D anomalous diffusion. The PSDD is imaged using a direct tomographic method based on Raman velocity selection. It…

原子物理 · 物理学 2017-08-16 Gadi Afek , Jonathan Coslovsky , Arnaud Courvoisier , Oz Livneh , Nir Davidson

I report recent results of numerical simulations designed to study the inner structure of Cold Dark Matter (CDM) halos. This work confirms the proposal of Navarro, Frenk & White (NFW) that the shape of LambdaCDM halo mass profiles differs…

天体物理学 · 物理学 2007-05-23 Julio F. Navarro

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 explore the possibility that the density profiles of elliptical galaxies and cold dark matter (CDM) halos found in cosmological simulations can be understood in terms of the same physical process, collisionless gravitational collapse. To…

宇宙学与河外天体物理 · 物理学 2012-06-27 Eli Visbal , Abraham Loeb , Lars Hernquist

We examine the coarse-grained phase-space density profiles of a set of recent, high-resolution simulations of galaxy-sized Cold Dark Matter (CDM) halos. Over two and a half decades in radius the phase-space density closely follows a…

天体物理学 · 物理学 2009-11-06 James E. Taylor , Julio F. Navarro

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…

宇宙学与河外天体物理 · 物理学 2023-02-08 A. Biviano , G. A. Mamon

It has been known for nearly 20 years that the pseudo phase-space density profile of equilibrium simulated dark matter halos, $\rho(r)/\sigma^3(r)$, is well described by a power law over 3 decades in radius, even though both the density…

宇宙学与河外天体物理 · 物理学 2020-04-16 Arpit Arora , Liliya L. R. Williams

We study the mass, velocity dispersion, and anisotropy profiles of $\Lambda$CDM halos using a suite of N-body simulations of unprecedented numerical resolution (the {\it Aquarius Project}). Our analysis confirms a number of results claimed…

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…

宇宙学与河外天体物理 · 物理学 2012-10-31 C. Alard

We use techniques from nonparametric function estimation theory to extract the density profiles, and their derivatives, from a set of N-body dark matter halos. We consider halos generated from LCDM simulations of gravitational clustering,…

天体物理学 · 物理学 2012-04-26 David Merritt , Alister W. Graham , Ben Moore , Juerg Diemand , Balsa Terzic

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…

天体物理学 · 物理学 2009-11-13 Steffen R. Knollmann , Alexander Knebe , Yehuda Hoffman

We investigate the connection between collisionless equilibria and the phase-space relation between density $\rho$ and velocity dispersion $\sigma$ found in simulations of dark matter halo formation, $F=\psd \propto r^{-\alpha}$.…

天体物理学 · 物理学 2009-11-13 Eric I. Barnes , Liliya L. R. Williams , Arif Babul , Julianne J. Dalcanton

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…

宇宙学与河外天体物理 · 物理学 2021-03-17 Stéphane Colombi

We study the pseudo phase-space density, $\rho(r)/\sigma^3(r)$, of $\Lambda$CDM dark matter halos with and without baryons (baryons+DM, and pure DM), by using the model introduced in Del Popolo (2009), which takes into account the effect of…

宇宙学与河外天体物理 · 物理学 2015-06-03 A. Del Popolo

We investigate non-linear scaling relations for two-dimensional gravitational collapse in an expanding background using a 2D TreePM code and study the strongly non-linear regime ($\bar\xi \leq 200$) for power law models. Evolution of these…

天体物理学 · 物理学 2007-05-23 S. Ray , J. S. Bagla , T. Padmanabhan

We show that the two basic assumptions of the model recently proposed by Manrique and coworkers for the universal density profile of cold dark matter (CDM) halos, namely that these objects grow inside out in periods of smooth accretion and…

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