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Related papers: Halo Profile Evolution and Velocity Bias

200 papers

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

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

Context:Halo formation time, which quantifies the mass assembly history of dark-matter halos, directly impacts galaxy properties and evolution. Although not directly observable, it can be inferred through proxies like star formation history…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-13 Atulit Srivastava , Weiguang Cui , Daniel de Andres , Jesse B. Golden-Marx , Elena Rasia , Ying Zu

We present useful functions for the profiles of dark-matter (DM) haloes with a free inner slope, from cusps to cores, where the profiles of density, mass-velocity and potential are simple analytic expressions. Analytic velocity is obtained…

Astrophysics of Galaxies · Physics 2017-04-12 Avishai Dekel , Guy Ishai , Aaron A. Dutton , Andrea V. Maccio

We build a simple analytical model for the bias of dark matter halos that applies to objects defined by an arbitrary density threshold, $200\leq\deltas\leq 1600$, and that provides accurate predictions from low-mass to high-mass halos. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Patrick Valageas

The density profiles of dark matter haloes can potentially probe dynamics, fundamental physics, and cosmology, but some of the most promising signals reside near or beyond the virial radius. While these scales have recently become…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-29 Benedikt Diemer

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

The mean matter density within the turnaround radius, which is the boundary that separates a nonexpanding structure from the Hubble flow, was recently proposed as a novel cosmological probe. According to the spherical collapse model, the…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-14 Giorgos Korkidis , Vasiliki Pavlidou , Konstantinos Tassis

In this paper, we analyze the dynamical evolution of quintessence dark energy induced by the collapse of dark matter halos. Different from other previous studies, we develop a numerical strategy which allows us to calculate the dark energy…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-09 Qiao Wang , Zuhui Fan

We split the total matter fluid into a bound (halo) component and an unbound (free particles) fluid component that is accreted by the halos. We adopt a different framework that treats the structure formation problem as a gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-18 Geoffrey Okeng'o , Nceba Mhlahlo , Roy Maartens

We introduce a new method to calculate dark matter halo density profiles from simulations. Each particle is 'smeared' over its orbit to obtain a dynamical profile that is averaged over a dynamical time, in contrast to the traditional…

Astrophysics of Galaxies · Physics 2024-01-26 Claudia Muni , Andrew Pontzen , Jason L. Sanders , Martin P. Rey , Justin I. Read , Oscar Agertz

We have carried out a comparative analysis of the properties of dark matter halos in N-body and hydrodynamical simulations. We analyze their density profiles, shapes and kinematical properties with the aim of assessing the effects that…

Astrophysics · Physics 2009-10-30 P. B. Tissera , R. Dom\ci nguez-Tenreiro

We simulate the growth of isolated dark matter haloes from self-similar and spherically symmetric initial conditions. Our N-body code integrates the geodesic deviation equation in order to track the streams and caustics associated with…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Mark Vogelsberger , Simon D. M. White , Roya Mohayaee , Volker Springel

We present a proposal for the full phase space distribution of the Milky Way halo. The model is axially and reflection symmetric and its time evolution is self-similar. It describes the halo as a set of discrete dark matter flows with…

Astrophysics · Physics 2009-02-20 L. D. Duffy , P. Sikivie

We present estimates of the nonlinear bias of cosmological halo formation, spanning a wide range in the halo mass from $\sim 10^{5} M_\odot$ to $\sim 10^{12} M_\odot$, based upon both a suite of high-resolution cosmological N-body…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Kyungjin Ahn , Ilian T. Iliev , Paul R. Shapiro , ChaiChalit Srisawat

We study the evolution of the cross-correlation between voids and the mass density field - i.e. of void profiles. We show that approaches based on the spherical model alone miss an important contribution to the evolution on large scales of…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-09 Elena Massara , Ravi K. Sheth

The first dark matter halos form by direct collapse from peaks in the matter density field, and evidence from numerical simulations and other analyses suggests that the dense inner regions of these objects largely persist today. These halos…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-24 M. Sten Delos , Margie Bruff , Adrienne L. Erickcek

The orbital parameters of dark matter (DM) subhaloes play an essential role in determining their mass-loss rates and overall spatial distribution within a host halo. Haloes in cosmological simulations grow by a combination of relatively…

Astrophysics of Galaxies · Physics 2021-02-17 Go Ogiya , James E. Taylor , Michael J. Hudson

We investigate the formation of virialized halos due to the gravitational collapse of collisionless matter using high-resolution N-body simulations. A variety of formation scenarios are studied, ranging from hierarchical clustering to…

Astrophysics · Physics 2009-10-30 Andreas Huss , Bhuvnesh Jain , Matthias Steinmetz

Density profiles are important tools in galaxy cluster research, offering insights into clusters dynamical states and their relationship with the broader Universe. While these profiles provide valuable information about the matter content…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-12 Giorgos Korkidis , Vasiliki Pavlidou