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Related papers: Evolution of Phase-Space Density in Dark Matter Ha…

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We use numerical simulations in a Lambda CDM cosmology to model density profiles in a set of 16 dark matter haloes with resolutions of up to 7 million particles within the virial radius. These simulations allow us to follow robustly the…

A halo model is presented which possesses a constant phase space density (Q) core followed by a radial CDM-like power law decrease in Q. The motivation for the core is the allowance for a possible primordial phase space density limit such…

Astrophysics · Physics 2009-11-13 F. D. A. Hartwick

We analyze the physical justification of the picture proposed by Salvador-Sole et al. in these proceedings for the time evolution of the universal density profile of dark-matter halos. According to this picture, halos have at formation a…

Astrophysics · Physics 2007-05-23 G. Gonzalez-Casado , A. Raig , E. Salvador-Sole

Although high-resolution N-body simulations make robust empirical predictions for the density distribution within cold dark matter halos, these studies have yielded little physical insight into the origins of the distribution. We…

Astrophysics · Physics 2008-11-26 Liliya L. R. Williams , Arif Babul , Julianne J. Dalcanton

Primordial dark matter (DM) haloes are the smallest gravitationally bound DM structures from which the first stars, black holes, and galaxies form and grow in the early universe. However, their structures are sensitive to the free streaming…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-03 Go Ogiya , Daisuke Nagai , Tomoaki Ishiyama

Navarro, Frenk, and White have suggested that the density profiles of simulated dark matter halos have a ``universal'' shape so that a given halo can be characterized by a single free parameter which fixes its mass. In this paper, we…

Astrophysics · Physics 2009-10-30 Richard N. Henriksen , Lawrence M. Widrow

We use a cosmological simulation of the Local Group to make quantitative and speculative predictions for direct detection experiments. Cold dark matter (CDM) halos form via a complex series of mergers, accretion events and violent…

We study the formation of the Milky Way's halo in a $\Lambda$CDM cosmology by scaling down a high resolution simulation of the formation of a cluster of galaxies. We determine how much phase-space substructure is left over from the objects…

Astrophysics · Physics 2009-09-25 Amina Helmi , Simon D. M. White , Volker Springel

For a spherical dark matter halo with isotropic velocity distribution, the phase space distribution function (DF), the energy distribution, and the density profile form a set of self-consistent description of its equilibrium state, and…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-26 Axel Gross , Zhaozhou Li , Yong-Zhong Qian

We study the effects of mass and force resolution on the density profiles of galaxy-size Cold Dark Matter (CDM) halos in a flat, low-density cosmological model with vacuum energy. We show thatalthough increasing the mass and force…

Astrophysics · Physics 2008-11-26 Anatoly Klypin , Andrey V. Kravtsov , James Bullock , Joel Primack

Dark matter haloes in Lambda CDM simulations grow by mergers with other haloes as well as accretion of "diffuse" non-halo material. We quantify the mass growth rates via these two processes, dM_mer/dt and dM_dif/dt, and their dependence on…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Onsi Fakhouri , Chung-Pei Ma

We study the imprint of Dark Energy on the density profile of Dark Matter halos using a set of high-resolution large volume cosmological N-body simulations from the Dark Energy Universe Simulation Series (DEUSS). We first focus on the…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-03 Irène Balmès , Yann Rasera , Pier-Stefano Corasaniti , Jean-Michel Alimi

N-body simulations of Cold Dark Matter (CDM) have shown that, in this hierarchical structure formation model, dark matter halo properties, such as the density profile, the phase-space density profile, the distribution of axial ratio, the…

Astrophysics · Physics 2015-05-13 Jie Wang , Simon D. M. White

Dark matter (DM) haloes forming near the thermal cut-off scale of the density perturbations are unique, since they are the smallest objects and form through monolithic gravitational collapse, while larger haloes contrastingly have…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-06 Go Ogiya , Oliver Hahn

We model the evolution of the mean galaxy occupation of dark-matter halos over the range $0.1<z<1.3$, using the data from the VIMOS-VLT Deep Survey (VVDS). The galaxy projected correlation function $w_p(r_p)$ was computed for a set of…

[abridged] In the dark matter (DM) halos embedding galaxies and galaxy systems the `entropy' K = \sigma^2 / \rho^{2/3} (a quantity that combines the radial velocity dispersion \sigma with the density \rho) is found from intensive N-body…

Astrophysics · Physics 2011-02-11 A. Lapi , A. Cavaliere

The evolution of a dark matter halo in a dark matter only simulation is governed purely byNewtonian gravity, making a clean testbed to determine what halo properties drive its fate.Using machine learning, we predict the survival, mass loss,…

Astrophysics of Galaxies · Physics 2021-04-07 Abigail Petulante , Andreas A. Berlind , J. Kelly Holley-Bockelmann , Manodeep Sinha

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 explore the effects of small scale structure on the formation and equilibrium of dark matter halos in a universe dominated by vacuum energy. We present the results of a suite of four N-body simulations, two with a LCDM initial power…

Astrophysics · Physics 2011-02-11 Michael T. Busha , August E. Evrard , Fred C. Adams

Formation of halos in the Dark Ages from initial spherical perturbations is analyzed in a four component Universe (dark matter, dark energy, baryonic matter and radiation) in the approximation of relativistic hydrodynamics. Evolution of…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-29 Bohdan Novosyadlyj , Valerii Shulga , Wei Han , Yurij Kulinich , Maxym Tsizh