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Related papers: Velocity dispersion profile in dark matter halos

200 papers

We present the results of a study of the average mass profile around galaxies using weak gravitational lensing. We use 45.5 deg^2 of R_C band imaging data from the Red-Sequence Cluster Survey (RCS) and define a sample of 1.2\times 10^5…

Astrophysics · Physics 2007-05-23 Henk Hoekstra , Howard K. C. Yee , Michael D. Gladders

$N$-body simulations have unveiled several apparently universal properties of dark matter halos, including a cusped density profile, a power-law pseudo phase-space density $\rho/\sigma_r^3$, and a linear $\beta-\gamma$ relation between the…

Astrophysics · Physics 2011-02-11 Emmanuel Van Hese , Maarten Baes , Herwig Dejonghe

We identify a universal relation between the radial density slope \alpha (r) and the velocity anisotropy \beta (r) for equilibrated structures. This relation holds for a variety of systems, including disk galaxy mergers, spherical…

Astrophysics · Physics 2007-05-23 Steen H. Hansen , Ben Moore

Dark matter particles form halos that contribute the major part of the mass of galaxy clusters. The formation of these cosmological structures have been investigated both observationally and in numerical simulations, which have confirmed…

Astrophysics · Physics 2009-11-05 Ole Host

Numerical simulations indicate that cosmological halos display power-law radial profiles of pseudo phase-space density (PPSD), Q=rho/sigma^3, where rho is mass density and sigma velocity dispersion. We test these predictions using the…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-08 A. Biviano , G. A. Mamon

A longstanding puzzle of fundamental importance in modern cosmology has been the origin of the nearly universal density profiles of dark matter halos found in N-body simulations -- the so-called NFW profile. We show how this behavior may be…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-25 Neal Dalal , Yoram Lithwick , Michael Kuhlen

The spin, $\lambda$, of dark matter (DM) halos in cosmological simulations follows a log normal distribution and has little correlation with galaxy observables. As such, there is currently no way to infer the $\lambda$ parameter of…

Astrophysics of Galaxies · Physics 2021-12-22 A. Obreja , T. Buck , A. V. Macciò

We develop an analytic halo model for the distribution of dust around galaxies. The model results are compared with the observed surface dust density profile measured through reddening of background quasars in the Sloan Digital Sky Survey…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Shogo Masaki , Naoki Yoshida

The radial distribution of gas within galactic haloes is connected to the star formation rate and the nature of baryon-driven feedback processes. Using six variants of the hydrodynamic simulation Simba, we study the impact of different…

Astrophysics of Galaxies · Physics 2024-12-04 Daniele Sorini , Sownak Bose , Romeel Davé , Daniel Anglés-Alcázar

We construct a new family of models of our Galaxy in which dark matter and disc stars are both represented by distribution functions that are analytic functions of the action integrals of motion. The potential that is self-consistently…

Astrophysics of Galaxies · Physics 2016-12-14 David R. Cole , James Binney

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 velocity distribution of dark matter near the Earth is important for an accurate analysis of the signals in terrestrial detectors. This distribution is typically extracted from numerical simulations. Here we address the possibility of…

Astrophysics of Galaxies · Physics 2017-02-08 Andreas Eilersen , Steen H. Hansen , Xingyu Zhang

We study velocity moments of elliptical galaxies in the Coma cluster using Jeans equations. The dark matter distribution in the cluster is modelled by a generalised formula based upon the results of cosmological N-body simulations. Its…

Astrophysics · Physics 2009-09-29 Ewa L. Lokas , Gary A. Mamon

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

We review the most recent evidence for the amazing properties of the density distribution of dark matter around spiral galaxies. Their rotation curves, coadded according to the galaxy luminosity, conform to an universal profile which can be…

Astrophysics · Physics 2007-05-23 P. Salucci , A. Borriello

We argue that a universal density profile for dark matter halos arises as a natural consequence of hierarchical structure formation. It is a fixed point in the process of repeated mergers. We present analytic and numerical arguments for the…

Astrophysics · Physics 2008-02-03 D. Syer , Simon D. M. White

We study the diversity of the density profiles of dark matter halos based on a large set of high-resolution cosmological simulations of 256^3 particles. The cosmological models include four scale-free models and three representative cold…

Astrophysics · Physics 2009-10-31 Y. P. Jing

Dark matter (DM) halos formed in CDM cosmologies seem to be characterized by a power law phase-space density profile. The density of the DM halos is often fitted by the NFW profile but a better fit is provided by the Sersic fitting formula.…

Astrophysics · Physics 2009-11-13 Amir Zait , Yehuda Hoffman , Isaac Shlosman

Dark matter sub-halos that pass near or through a thin tidal star stream locally increase its velocity dispersion. Subsequent orbital evolution further increases the velocity dispersion and stream width, lowering the surface density of a…

Astrophysics of Galaxies · Physics 2023-07-06 Raymond G. Carlberg , Hayley Agler

Satellite galaxies are commonly used as tracers to measure the line-of-sight velocity dispersion ($\sigma_{\rm LOS}$) of the dark matter halo associated with their central galaxy, and thereby to estimate the halo's mass. Recent…

Astrophysics of Galaxies · Physics 2018-03-06 Pascal J. Elahi , Chris Power , Claudia del P. Lagos , Rhys Poulton , Aaron S. G. Robotham