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Related papers: Generating Equilibrium Dark Matter Halos: Inadequa…

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We use the universal mass accretion history recently reported for simulations of halo formation in the cold dark matter model (CDM) to analyze the formation and growth of a single halo. We derive the time-dependent density profile three…

Astrophysics · Physics 2007-05-23 Marcelo A. Alvarez , Kyungjin Ahn , Paul R. Shapiro

In this paper a prescription for generating an equilibrium spherical system depicted with cuspy density profiles is extended to a core density profile, the Burkert profile, which is observationally more suitable to dwarfs. By using a…

Astrophysics · Physics 2015-06-24 W-H Liu , Y-N Fu , Z-G Deng , J-H. Huang

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

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…

An iterative approach is used to construct spherically symmetric equilibrium models with an anisotropic velocity distribution. The potentialities of the method have been tested on models with known distribution functions, the…

Astrophysics · Physics 2009-11-13 N. Ya. Sotnikova , S. A. Rodionov

Dark-matter halos are the scaffolding around which galaxies and clusters are built. They form when the gravitational instability of primordial density fluctuations causes regions which are denser than average to slow their cosmic expansion,…

Astrophysics · Physics 2007-05-23 Paul R. Shapiro , Ilian T. Iliev , Hugo Martel , Kyungjin Ahn , Marcelo A. Alvarez

We propose a model for how the buildup of dark halos by merging satellites produces a characteristic inner cusp, of a density profile \rho \prop r^-a with a -> a_as > 1, as seen in cosmological N-body simulations of hierarchical clustering…

Astrophysics · Physics 2009-11-07 Avishai Dekel , Itai Arad , Jonathan Devor , Yuval Birnboim

Adaptive SPH and N-body simulations were carried out to study the evolution of the equilibrium structure of dark matter halos that result from the gravitational instability and fragmentation of cosmological pancakes. Such halos resemble…

Astrophysics · Physics 2009-11-06 Marcelo Alvarez , Paul R. Shapiro , Hugo Martel

The structural evolution of substructure in cold dark matter (CDM) models is investigated combining ``low-resolution'' satellites from cosmological N-body simulations of parent halos with N=10^7 particles with high-resolution individual…

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

In order to study their interplay with large scale cosmic evolution and with relativistic effects, such as gravitational lenses, quintessence sources or gravitational waves, we construct a post-Newtonian fluid framework for the…

Astrophysics · Physics 2009-08-18 Tonatiuh Matos , Dario Nunez , Roberto A Sussman

Dark Matter (DM) direct detection experiments usually assume the simplest possible 'Standard Halo Model' for the Milky Way (MW) halo in which the velocity distribution is Maxwellian. This model assumes that the MW halo is an isotropic,…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-02 Mattia Fornasa , Anne M. Green

We perform collisionless N-body simulations of 1:1 galaxy mergers, using models which include a galaxy halo, disc and bulge, focusing on the behaviour of the halo component. The galaxy models are constructed without recourse to a Maxwellian…

Astrophysics · Physics 2008-11-26 P. J. McMillan , E. Athanassoula , W. Dehnen

We report a series of high-resolution cosmological N-body simulations designed to explore the formation and properties of dark matter halos with masses close to the damping scale of the primordial power spectrum of density fluctuations. We…

Astrophysics · Physics 2009-11-13 P. Colin , O. Valenzuela , V. Avila-Reese

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…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-27 Eli Visbal , Abraham Loeb , Lars Hernquist

We present an entirely analytic model for a preheated, polytropic intergalactic medium in hydrostatic equilibrium within a NFW dark halo potential in which the evolution of the halo structure between major merger events proceeds inside-out…

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,…

Astrophysics · Physics 2012-04-26 David Merritt , Alister W. Graham , Ben Moore , Juerg Diemand , Balsa Terzic

We discuss various aspects of the inner structure formation in virialized dark matter (DM) halos that form as primordial density inhomogeneities evolve in the cosmological standard model. The main focus is on the study of central…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-04 A. G. Doroshkevich , V. N. Lukash , E. V. Mikheeva

Self-gravitating astronomical objects often show a central plateau in the density profile (core) whose physical origin is hotly debated. Cores are theoretically expected in N-body systems of maximum entropy, however, they are not present in…

Astrophysics of Galaxies · Physics 2021-04-28 Jorge Sanchez Almeida , Ignacio Trujillo

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
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