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Related papers: Halo Shapes and their Relation to Environment

200 papers

We study the phase-space structure of a dark-matter halo formed in a high resolution simulation of a Lambda CDM cosmology. Our goal is to quantify how much substructure is left over from the inhomogeneous growth of the halo, and how it may…

Astrophysics · Physics 2009-09-25 Amina Helmi , Simon D. M. White , Volker Springel

The hierarchical mergers that form the haloes of dark matter surrounding galaxies, groups and clusters are not entirely efficient, leaving substantial amounts of dense substructure, in the form of stripped halo cores or `subhaloes',…

Astrophysics · Physics 2009-11-07 James E. Taylor , Arif Babul

Dark matter could be composed of macroscopic objects with large masses and geometric cross-sections spanning many decades. We investigate the potential interaction of such `stuff-sized' dark matter by considering its interactions with…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-22 Zachary S. C. Picker

We present a technique for constructing equilibrium triaxial N-body haloes with nearly arbitrary density profiles, axial ratios and spin parameters. The method is based on the way in which structures form in hierarchical cosmological…

Astrophysics · Physics 2009-11-10 Ben Moore , Stelios Kazantzidis , Juerg Diemand , Joachim Stadel

We present a detailed non-spherical modeling of dark matter halos on the basis of a careful analysis of state-of-the art N-body simulations. The fitting formulae presented here form a complete and accurate description of the triaxial…

Astrophysics · Physics 2007-05-23 Y. P. Jing

The evolution of halos consisting of weakly self-interacting dark matter particles is summarized. The halos initially contain a central density cusp as predicted by cosmological models. Weak self-interaction leads to the formation of an…

Astrophysics · Physics 2007-05-23 Andreas Burkert

A massive, self-interacting scalar field has been considered as a possible candidate for the dark matter in the universe. We present an observational constraint to the model arising from strong lensing observations in galaxies. The result…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-18 Alma X. Gonzalez-Morales , Alberto Diez-Tejedor , L. Arturo Urena-Lopez , Octavio Valenzuela

Observations of density profiles of galaxies and clusters constrain the properties of dark matter. Formation of stable halos by collisional fluids with very low mass particles appears as the most probable interpretation, while halos formed…

General Physics · Physics 2011-04-14 Ernst Fischer

Recently there has been a lot of attention focussed on a virialized halo-based approach to understanding the properties of the matter and galaxy power spectrum. A key ingredient in this model is the number and distribution of galaxies…

Astrophysics · Physics 2009-10-31 Martin White , Lars Hernquist , Volker Springel

We study the formation and evolution of the dark matter halos in a LCDM model. The dynamics of 16.8 million DM particles is followed numerically in a box of 60 Mpc/h with the dynamic range of 32,000 in spatial resolution. The high…

Astrophysics · Physics 2007-05-23 S. Gottloeber , A. A. Klypin , A. V. Kravtsov

We investigate the evolution of dark matter halo shapes in cosmological N-body simulations both in scale free Einstein-De Sitter (EdS) and $\Lambda$CDM cosmologies. We compute the axis ratios ($q=b/a,s=c/a$) of well resolved central halos…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-03 Ayan Nanda , Nishikanta Khandai , J. S. Bagla , Swati Gavas

We use numerical simulations to examine the substructure within galactic and cluster mass halos that form within a hierarchical universe. Clusters are easily reproduced with a steep mass spectrum of thousands of substructure clumps that…

The evolution of halos consisting of weakly self-interacting dark matter particles is investigated using a new numerical Monte-Carlo N-body method. The halos initially contain kinematically cold, dense 1/r-power-law cores. For interaction…

Astrophysics · Physics 2009-10-31 Andreas Burkert

We present evidence that all galaxies, of any Hubble type and luminosity, bear the kinematical signature of a mass component distributed differently from the luminous matter. We review and/or derive the DM halo properties of galaxies of…

Astrophysics · Physics 2007-05-23 Paolo Salucci , Massimo Persic

In a serie of three papers, the dynamical interplay between environments and dark matter haloes is investigated, while focussing on the dynamical flows through their virial sphere. Our method relies on both cosmological simulations, to…

Astrophysics · Physics 2008-11-26 Dominique Aubert , Christophe Pichon

It has been shown that the dissipative gas infall during galaxy formation has the capability to modify the shape of dark matter halos. In this paper we perform the first detailed analysis of particle orbits in a cosmological dark matter…

Astrophysics · Physics 2007-05-23 Andrea V. Maccio' , Ioannis Sideris , Marco Miranda , Ben Moore , Roland Jesseit

Tidal gravitational forces can modify the shape of galaxies and clusters of galaxies, thus correlating their orientation with the surrounding matter density field. We study the dependence of this phenomenon, known as intrinsic alignment…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-06 Davide Piras , Benjamin Joachimi , Björn Malte Schäfer , Mario Bonamigo , Stefan Hilbert , Edo van Uitert

In this study, we investigate the impact of dark matter on the structure and deformation of magnetars. We assume a perturbative approach for the magnetic field deformation and that the dark matter only interacts gravitationally with…

High Energy Astrophysical Phenomena · Physics 2025-09-24 Asit karan , Anil Kumar , Monika Sinha , Ritam Mallick

Using observational data for a sample of dark matter dominated galaxies and two cluster of galaxies, we have found that the central halo density does not depend on its mass, and the core radius is roughly proportional to the maximum…

Astrophysics · Physics 2007-05-23 V. Avila-Reese , C. Firmani , E. D'Onghia , X. Hernandez

High-quality optical rotation curves for a sample of low-luminosity spirals evidence that the dark halos around galaxies are inconsistent with the output of proper CDM simulations. In fact, dark halos enveloping stellar disks are structures…

Astrophysics · Physics 2009-11-06 P. Salucci , A. Borriello