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Related papers: Self-Similar Spherical Collapse with Tidal Torque

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We examine the nonlinear structure of gravitationally collapsed objects that form in our simulations of wavelike cold dark matter ($\psi$DM), described by the Schr\"{o}dinger-Poisson (SP) equation with a particle mass $\sim 10^{-22} {\rm…

We develop a model for the growth of dark matter halos and use it to study their evolved density profiles. In this model, halos are spherical and form by quiescent accretion of matter in clumps, called satellites. The halo mass as a…

Astrophysics · Physics 2009-10-30 Adi Nusser , Ravi Sheth

We study the angular momentum profile of dark matter halos for a statistical sample drawn from a set of high-resolution cosmological simulations of $256^3$ particles. Two typical Cold Dark Matter (CDM) models have been analyzed, and the…

Astrophysics · Physics 2009-11-07 D. N. Chen , Y. P. Jing

We analyse modelling techniques for the large-scale structure formed in scalar-tensor theories of constant Brans-Dicke parameter which match the concordance model background expansion history and produce a chameleon suppression of the…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-14 Lucas Lombriser , Kazuya Koyama , Baojiu Li

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…

We have developed a new halo finding method, Physically Self-Bound (PSB) group finding algorithm, which can efficiently identify halos located even at crowded regions. This method combines two physical criteria such as the tidal radius of a…

Astrophysics · Physics 2009-11-10 Juhan Kim , Changbom Park

I propose a modification of the spherical infall model for the evolution of density fluctuations with initially Gaussian probability distribution and scale-free power spectra. I introduce a generalized form of the initial density…

Astrophysics · Physics 2007-05-23 Ewa L. Lokas

Dark-matter haloes do not form in isolation but within the surrounding cosmic web. By the time a halo begins to collapse, its larger-scale environment has typically collapsed along two axes, forming filaments that channel anisotropic infall…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-06 Junsup Shim , Dmitri Pogosyan , Myoungwon Jeon , Christophe Pichon

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 compare the dark matter halos' structural parameters derived for four Milky Way dwarf spheroidal galaxies to those of subhalos found in cosmological $N$-body simulations. We confirm that estimates of the mass at a single fixed radius are…

Astrophysics of Galaxies · Physics 2015-12-02 Maarten A. Breddels , Carlos Vera-Ciro , Amina Helmi

We present a new algorithm which groups the subhaloes found in cosmological N- body simulations by structure finders such as SUBFIND into dark matter haloes whose formation histories are strictly hierarchical. One advantage of these…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Lilian Jiang , John C. Helly , Shaun Cole , Carlos S. Frenk

Context. The shapes of dark matter halos can be used to constrain the fundamental properties of dark matter. In standard Cold Dark Matter (CDM) cosmologies, halos are typically triaxial, with a preference for prolate configurations,…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-25 C. Giocoli , G. Despali , L. Moscardini , M. Meneghetti , R. K. Sheth , A. Pillepich , M. Vogelsberger

N-body simulations that follow only a collisionless dark matter component have failed to produce galaxy halos or substructure within dense environments. We investigate the `over-merging' problem analytically and with numerical simulations,…

Astrophysics · Physics 2009-10-28 Ben Moore , Neal Katz , George Lake

We investigate the formation of spherical cosmological structures following both dark matter and gas components. We focus on the dynamical aspect of the collapse assuming an adiabatic, $\gamma = 5/3$, fully ionized primordial plasma. We use…

Astrophysics · Physics 2009-10-30 Jean-Pierre CHIEZE , Romain Teyssier , Jean-Michel Alimi

We present a comprehensive set of convergence tests which explore the role of various numerical parameters on the equilibrium structure of a simulated dark matter halo. We report results obtained with two independent, state-of-the-art,…

Astrophysics · Physics 2008-11-26 C. Power , J. F. Navarro , A. Jenkins , C. S. Frenk , S. D. M. White , V. Springel , J. Stadel , T. Quinn

Using a series of high-resolution N-body simulations of the concordance cosmology we investigate how the formation histories, shapes and angular momenta of dark-matter haloes depend on environment. We first present a classification scheme…

Astrophysics · Physics 2008-11-26 Oliver Hahn , Cristiano Porciani , C. Marcella Carollo , Avishai Dekel

We study the imprints on the formation of cosmic structures of a particular class of dark energy parameterizations dubbed PADE parameterization. Here we investigate how dark energy can affect the growth of large scale structures of the…

General Relativity and Quantum Cosmology · Physics 2019-05-07 Mehdi Rezaei

The observed flaring of HI disk in the outer region of galaxies has been used in the past to determine the shape of the dark matter halo. Previous studies based on this concept suggest a slightly oblate halo (axis ratio ~ 0.8) for our…

Astrophysics · Physics 2009-11-11 C. A. Narayan , K. Saha , C. J. Jog

Cosmological models in which dark matter consists of cold elementary particles predict that the dark halo population should extend to masses many orders of magnitude below those at which galaxies can form. Here we report a cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-23 Jie Wang , Sownak Bose , Carlos S. Frenk , Liang Gao , Adrian Jenkins , Volker Springel , Simon D. M. White

We use the NIHAO simulations to investigate the effects of baryonic physics on the time evolution of Dark Matter central density profiles. The sample is made of $\approx 70$ independent high resolution hydrodynamical simulations of galaxy…