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(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

We have recently shown that both the Prugniel-Simien model and Sersic's function (hereafter referred to as the Einasto model when applied to internal density profiles) describe simulated dark matter halos better than an NFW-like model with…

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

Recent high-resolution N-body CDM simulations indicate that nonsingular three-parameter models such as the Einasto profile perform better than the singular two-parameter models, e.g. the Navarro, Frenk and White, in fitting a wide range of…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-24 E. Retana-Montenegro , E. Van Hese , G. Gentile , M. Baes , F. Frutos-Alfaro

N-body simulations find a universal structure for the halos which result from the nonlinear growth of Gaussian-random-noise density fluctuations in the CDM universe. This talk summarized our attempts to derive and explain this universal…

Astrophysics · Physics 2016-08-30 Paul R. Shapiro , Kyungjin Ahn , Marcelo Alvarez , Ilian T. Iliev , Hugo Martel

We propose a new numerical procedure to simulate a single dark halo of any size and mass in a hierarchical framework coupling the extended Press-Schechter formalism (EPSF) to N-body simulations. The procedure consists of assigning…

Astrophysics · Physics 2009-11-07 Elena D'Onghia , Claudio Firmani , Guido Chincarini

We review some properties of the stationary states of the Fokker - Planck equation for N interacting particles within a mean field approximation, which yields a non-linear integrodifferential equation for the particle density. Analytical…

Statistical Mechanics · Physics 2009-11-07 N. Martzel , C. Aslangul

We address the issue of the proximity of interacting diffusion models on large graphs with a uniform degree property and a corresponding mean field model, i.e. a model on the complete graph with a suitably renormalized interaction…

Probability · Mathematics 2016-11-23 Sylvain Delattre , Giambattista Giacomin , Eric Luçon

We use the Made-to-Measure method to construct N-body realizations of self-similar, triaxial ellipsoidal halos having cosmologically realistic density profiles. Our implementation parallels previous work with a few numerical refinements,…

Astrophysics of Galaxies · Physics 2015-06-23 J. C. Malvido , J. A. Sellwood

Recent N-body simulations have shown that Einasto radial profiles provide the most accurate description of dark matter halos. Predictions based on the traditional NFW functional form may fail to describe the structural properties of cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-27 Mauro Sereno , Cosimo Fedeli , Lauro Moscardini

We use high-resolution N-body simulations to study the equilibrium density profiles of dark matter halos in hierarchically clustering universes. We find that all such profiles have the same shape, independent of halo mass, of initial…

Astrophysics · Physics 2008-11-26 Julio F. Navarro , Carlos S. Frenk , Simon D. M. White

Conventional studies of galaxy clustering within the framework of halo models typically assume that the density profile of all dark matter haloes can be approximated by the Navarro-Frenk-White (NFW) spherically symmetric profile. However,…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-09 Anna Durkalec , Agnieszka Pollo , Ummi Abbas

We study the long time behaviour of the kinetic Fokker-Planck equation with mean field interaction, whose limit is often called Vlasov-Fkker-Planck equation. We prove a uniform (in the number of particles) exponential convergence to…

Analysis of PDEs · Mathematics 2019-12-06 Arnaud Guillin , Wei Liu , Liming Wu , Chaoen Zhang

Cosmological simulations of galaxy formation often rely on prescriptions for star formation and feedback that depend on halo properties such as halo mass, central over-density, and virial temperature. In this paper we address the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 M. Trenti , B. D. Smith , E. J. Hallman , S. W. Skillman , J. M. Shull

Gravitational amplification of Poisson noise in stellar systems increases the dipole noise power by roughly a factor of six and the quadrupole noise by 50% for a King model profile. The dipole noise is amplified by a factor of fifteen for…

Astrophysics · Physics 2009-10-30 Martin D. Weinberg

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

Only through resonances can non-axisymmetric features such as spiral arms and bars exert torques over large scales and change the overall structure of a near-equilibrium galaxy. We describe the resonant interaction mechanism in detail and…

Astrophysics · Physics 2008-11-26 Martin D. Weinberg , Neal Katz

Simple simulations suggest that the phase space structure of haloes identified in cosmological calculations is invariant under the dynamics induced by sinking substructure satellites -- the background expands so as to leave the total…

Astrophysics · Physics 2007-05-23 Amr El-Zant

N-body simulations predict that dark matter haloes are described by specific density profiles on both galactic- and cluster-sized scales. Weak gravitational lensing through the measurements of their first and second order properties, shear…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 E. Retana-Montenegro , F. Frutos-Alfaro , M. Baes

Dark-matter halos grown in cosmological simulations appear to have central NFW-like density cusps with mean values of $d\log\rho/d\log r \approx -1$, and some dispersion, which is generally parametrized by the varying index $\alpha$ in the…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-15 Jens Hjorth , Liliya L. R. Williams , Radosław Wojtak , Michael McLaughlin

The latest cosmological N-body simulations find two intriguing properties for dark matter haloes: (1) their radial density profile, rho, is better fit by a form that flattens to a constant at the halo center (the Einasto profile) than the…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-21 Chung-Pei Ma , Philip Chang , Jun Zhang