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Related papers: Galactic cannibalism and CDM density profiles

200 papers

In hierarchical cosmologies the evolution of galaxy clustering depends both on cosmological quantities such as Omega and Lambda, which determine how dark matter halos form and evolve, and on the physical processes - cooling, star formation…

We present results of large N-body-hydrodynamic simulations of galaxy formation. Our simulations follow the formation of galaxies in cubic volumes of side 100Mpc, in two versions of the cold dark matter (CDM) cosmogony: the standard,…

Observations of a flat density profile in the cores of dark-matter-dominated halos on the two extremes of mass for virialized objects in the universe, dwarf galaxies and galaxy clusters, present a serious challenge to the current standard…

Astrophysics · Physics 2009-10-31 Paul R. Shapiro , Ilian T. Iliev

We examine two extreme models for the build-up of the stellar component of luminous elliptical galaxies. In one case, we assume the build-up of stars is dissipational, with centrally accreted gas radiating away its orbital and thermal…

Astrophysics of Galaxies · Physics 2015-05-18 Claire N. Lackner , Jeremiah P. Ostriker

Recent Strong lensing data and rotation curves of dwarf galaxies indicate that many galactic clusters may have a soft core instead of a central cusp in their density distribution. This result challenges the standard CDM (Cold Dark Matter)…

Astrophysics · Physics 2007-05-23 M. H. Chan , M. C. Chu

We reanalyze the galaxy-mass correlation function measured by the Sloan Digital Sky Survey to obtain host dark matter halo masses at galaxy and galaxy group scales. We extend the data to galaxy clusters in the 2MASS catalog and study the…

Astrophysics · Physics 2016-08-30 Asantha Cooray , Milos Milosavljevic

We present stellar and dark matter (DM) density profiles for a sample of seven massive, relaxed galaxy clusters derived from strong and weak gravitational lensing and resolved stellar kinematic observations within the centrally-located…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Andrew B. Newman , Tommaso Treu , Richard S. Ellis , David J. Sand

We address the question of how well the density profile of galaxy clusters can be determined by combining strong lensing and velocity dispersion data. We use cosmological dark matter simulations of clusters to test the reliability of the…

Astrophysics · Physics 2010-12-01 M. Meneghetti , M. Bartelmann , A. Jenkins , C. Frenk

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

We have simulated the growth of structure in two 100 Mpc boxes for LCDM and SCDM universes. These N-body/SPH simulations include a gaseous component which is able to cool radiatively. A fraction of the gas cools into cold dense objects…

We use N-body/gasdynamical LambdaCDM cosmological simulations to examine the effect of the assembly of a central galaxy on the shape and mass profile of its dark halo. Two series of simulations are compared; one that follows only the…

Astrophysics of Galaxies · Physics 2015-05-13 Mario G. Abadi , Julio F. Navarro , Mark Fardal , Arif Babul , Matthias Steinmetz

We study the formation of dark halos in a $\Lambda$CDM universe under the assumption that Cold Dark Matter particles have a finite cross-section for elastic collisions. We compare evolution when CDM mean free paths are comparable to halo…

Astrophysics · Physics 2011-07-18 Naoki Yoshida , Volker Springel , Simon D. M. White , Giuseppe Tormen

Using a sample of 425 nearby Brightest Cluster Galaxies (BCGs) from von der Linden et al. (2007), we study the relationship between their internal properties (stellar masses, structural parameters and morphologies) and their environment.…

Astrophysics of Galaxies · Physics 2016-08-08 Dongyao Zhao , Alfonso Aragón-Salamanca , Christopher J. Conselice

Cusp-core problem is a controversial problem on galactic dark matter haloes. Cosmological N-body simulations has demonstrated that galactic dark matter haloes have a cuspy density profile at the centre. However, baryonic physics may affect…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Shigeki Inoue , Takayuki R. Saitoh

We investigate the influence of the external tidal field of a dark matter halo on the dynamical evolution of star clusters using direct N-body simulations, where we assume that the halo is described by a Navarro, Frenk & White mass profile…

Astrophysics of Galaxies · Physics 2009-09-28 A. K. Praagman , J. R. Hurley , C. Power

Central galaxies (CGs) in galaxy groups and clusters are believed to form and assemble a good portion of their stellar mass at early times, but they also accrete significant mass at late times via galactic cannibalism, that is merging with…

Astrophysics of Galaxies · Physics 2017-01-25 Carlo Nipoti

Gravitational lensing observations of massive X-ray clusters imply a steep characteristic density profile marked by a central concentration of dark matter. The observed mass fraction within a projected radius of 150 kpc is twice that found…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Rennan Barkana , Abraham Loeb

Through a suite of direct N-body simulations, we explore how the structural and kinematic evolution of a star cluster located at the center of a dwarf galaxy is affected by the shape of its host's dark matter density profile. The stronger…

Astrophysics of Galaxies · Physics 2018-08-01 Jeremy J. Webb , Enrico Vesperini

A standard paradigm is now available for the recent evolution (z < 10) of structure on galactic and larger scales. Most of the matter is assumed to be dark and dissipationless and to cluster hierarchically from gaussian initial conditions.…

Astrophysics · Physics 2007-05-23 Simon D. M. White

We combine 10 high resolution resimulations of cluster--sized dark haloes with semi--analytic galaxy formation modelling in order to compare the number density and velocity dispersion profiles of cluster galaxies with those of dark matter…

Astrophysics · Physics 2009-09-25 Liang Gao , Gabriella De Lucia , Simon D. M. White , Adrian Jenkins