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Related papers: Halo Profile Evolution and Velocity Bias

200 papers

Can N-body simulations reliably determine the structural properties of dark matter halos? Focussing on a Virgo-sized galaxy cluster, we increase the resolution of current ``high resolution simulations'' by almost an order of magnitude to…

Astrophysics · Physics 2008-11-26 Sebastiano Ghigna , Ben Moore , Fabio Governato , George Lake , Tom Quinn , Joachim Stadel

We use the high resolution cosmological N-body simulations from the Aquarius project to investigate in detail the mechanisms that determine the shape of Milky Way-type dark matter haloes. We find that, when measured at the instantaneous…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Carlos A. Vera-Ciro , Laura V. Sales , Amina Helmi , Carlos S. Frenk , Julio F. Navarro , Volker Springel , Mark Vogelsberger , Simon D. M. White

We investigate statistically the dynamical consequences of cosmological fluxes of matter and related moments on progenitors of today's dark matter haloes. Their dynamics is described via canonical perturbation theory which accounts for two…

Astrophysics · Physics 2009-11-11 Christophe Pichon , Dominique Aubert

In the hierarchical structure formation model cosmic halos are supposed to form by accretion of smaller units along anisotropic direction, defined by large-scale filamentary structures. After the epoch of primary mass aggregation (which…

Astrophysics · Physics 2015-06-24 Manolis Plionis , Cinthia Ragone , Spyros Basilakos

In this work, we study the evolution of Betti curves obtained by persistent-homological analysis of point clouds formed by halos in different cosmological $N$-body simulations. We show that they can be approximated with a scaled log-normal…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-20 Vitalii Tymchyshyn , Maksym Tsizh , Franco Vazza , Marco Baldi

Among the most fundamental properties of a dark matter halo is its density profile. Motivated by the recent proposal by Garc\'ia et al. [R. Garc\'ia et. al., MNRAS 521, 2464 (2023)] to define a dynamical halo as the collection of orbiting…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-02 Tristen Shields , Edgar M. Salazar , Eduardo Rozo , Aakanksha Adya , Calvin Osinga , Ze'ev Vladimir

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

The radial mass distribution of dark matter haloes is investigated within the framework of the spherical infall model. We present a new formulation of spherical collapse including non-radial motions, and compare the analytical profiles with…

Astrophysics · Physics 2009-11-10 Y. Ascasibar , G. Yepes , S. Gottloeber , V. Mueller

We derive a semi-analytical extension of the spherical collapse model of structure formation that takes account of the effects of deviations from spherical symmetry and shell crossing which are important in the non-linear regime. Our model…

Astrophysics · Physics 2008-11-26 Douglas J. Shaw , David F. Mota

Using a generalized self-similar secondary infall model, which accounts for tidal torques acting on the halo, we analyze the velocity profiles of halos in order to gain intuition for N-body simulation results. We analytically calculate the…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-23 Phillip Zukin , Edmund Bertschinger

Accurately predicting the abundance and structural evolution of dark matter subhaloes is crucial for understanding galaxy formation, modeling galaxy clustering, and constraining the nature of dark matter. Due to the nonlinear nature of…

Astrophysics of Galaxies · Physics 2019-10-22 Sheridan B. Green , Frank C. van den Bosch

A mass of dark matter halo is commonly defined as the spherical over-density (SO) mass with respect to a reference density, whereas the time evolution of an SO mass can be affected by the redshift evolution of the reference density as well…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-25 Masato Shirasaki

We study the impact of numerical parameters on the properties of cold dark matter haloes formed in collisionless cosmological simulations. We quantify convergence in the median spherically-averaged circular velocity profiles for haloes of…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-12 Aaron D. Ludlow , Joop Schaye , Richard Bower

Based on the Millennium Simulation we examine assembly bias for the halo properties: shape, triaxiality, concentration, spin, shape of the velocity ellipsoid and velocity anisotropy. For consistency we determine all these properties using…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Andreas Faltenbacher , Simon D. M. White

We use dark matter haloes identified in the MareNostrum Universe and galaxy groups identified in the Sloan Data Release 7 galaxy catalogue, to study the relation between halo shape and halo dynamics, parametrizing out the mass of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 C. Ragone-Figueroa , M. Plionis , M. Merchan , S. Gottlober , G. Yepes

We explore the dynamical restrictions on the structure of dark matter halos through a study of cosmological self-similar gravitational collapse solutions. A fluid approach to the collisionless dynamics of dark matter is developed and the…

Astrophysics · Physics 2009-10-31 Kandaswamy Subramanian

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

High-Velocity Clouds (HVCs) are a major fuel reservoir for star formation in the Galactic disk. Determining their origin and kinematics is thus crucial for understanding Galactic evolution. In this paper, we employ simple test-particle…

Astrophysics of Galaxies · Physics 2026-04-28 Izumi Seno , Shu-ichiro Inutsuka , Jiro Shimoda

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

The structural and dynamic properties of the dark matter halos, though an important ingredient in understanding large-scale structure formation, require more conservative particle resolution than those required by halo mass alone in a…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-23 Sujatha Ramakrishnan , Premvijay Velmani