English
Related papers

Related papers: Radial orbit instability in dwarf dark matter halo…

200 papers

We use Fabry-Perot Halpha spectroscopy, complemented with published HI radio synthesis observations to derive high resolution rotation curves of spiral galaxies. We investigate precisely their inner mass distribution and compare it to CDM…

Astrophysics · Physics 2007-05-23 Sebastien Blais-Ouellette , Claude Carignan , Philippe Amram

We use a set of large cosmological N-body simulations to study the internal structure of dark matter haloes which form in scale-free models. We find that the radius r_178 corresponding to a mean interior overdensity of 178 accurately…

Astrophysics · Physics 2015-06-24 Shaun Cole , Cedric Lacey

We use N-body simulations of dark matter haloes in cold dark matter (CDM) and a large set of different warm dark matter (WDM) cosmologies to demonstrate that the spherically averaged density profile of dark matter haloes has a shape that…

Astrophysics of Galaxies · Physics 2015-05-20 E. Polisensky , M. Ricotti

In this paper, we study the dynamical stability and time evolution of the central dark matter cores of low-mass (about 10^8-10^9 M_solar) galactic haloes found in recent cold dark matter simulations at high redshift. From those simulations…

Astrophysics · Physics 2009-11-10 Massimo Ricotti , Mark I. Wilkinson

We use a set of cosmological N-body simulations to investigate the structural shape of galaxy-sized cold dark matter (CDM) halos. Unlike most previous work on the subject - which dealt with shapes as measured by the inertia tensor - we…

Astrophysics · Physics 2008-11-26 E. Hayashi , J. F. Navarro , V. Springel

We study how properties of discrete dark matter halos depend on halo environment, characterized by the mass density around the halos on scales from 0.5 to 16 $h^{-1}{\rm Mpc}$. We find that low mass halos (those less massive than the…

Astrophysics of Galaxies · Physics 2017-01-10 Christoph T Lee , Joel R. Primack , Peter Behroozi , Aldo Rodriguez-Puebla , Doug Hellinger , Avishai Dekel

Observational studies of galaxy isophotal shapes have shown that galaxy orientations are anisotropic: a galaxy's long axis tends to be oriented toward the center of its host. This radial alignment is seen across a wide range of scales, from…

Cosmology and Nongalactic Astrophysics · Physics 2010-09-23 Maria J. Pereira , Greg L. Bryan

The stability of rotating isotropic spherical stellar systems is investigated by using N-body simulations. Four spherical models with realistic density profiles are studied: one of them fits the luminosity profile of globular clusters,…

Astrophysics · Physics 2009-11-07 Andres Meza

The structure of dark matter halos as predicted from cosmological models is discussed and compared with observed rotation curves of dark matter-dominated dwarf galaxies. The theoretical models predict that dark matter halos represent a…

Astrophysics · Physics 2007-05-23 Andreas Burkert , Joseph Silk

Cold dark matter cosmogony predicts triaxial dark matter halos, whereas observations find quite round halos. This is most likely due to the condensation of baryons leading to rounder halos. We examine the halo phase space distribution basis…

The dynamical properties of spherically symmetric galaxy models, where a Jaffe (1983) stellar density profile is embedded in a total mass density decreasing as $r^{-3}$ at large radii, are presented. The orbital structure of the stellar…

Astrophysics of Galaxies · Physics 2019-10-02 L. Ciotti , A. Mancino , S. Pellegrini

Locating the position of periodic orbits in galaxies is undoubtedly an issue of paramount importance. We reveal the position and the stability of periodic orbits of stars moving in the meridional plane $(R,z)$ of an axially symmetric…

Astrophysics of Galaxies · Physics 2018-02-28 Euaggelos E. Zotos

The shapes of individual self-gravitating structures of an ensemble of identical, collisionless particles have remained elusive for decades. In particular, a reason why mass density profiles like the Navarro-Frenk-White or the Einasto…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-01 Jenny Wagner

We study nonaxisymmetric perturbations of rotating relativistic stars. modeled as perfect-fluid equilibria. Instability to a mode with angular dependence $\exp(im\phi)$ sets in when the frequency of the mode vanishes. The locations of these…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Nikolaos Stergioulas , John L. Friedman

We use the concept of the spiral rotation curves universality to investigate the luminous and dark matter properties of the dwarf disc galaxies in the local volume (size $\sim11$ Mpc). Our sample includes 36 objects with rotation curves…

Astrophysics of Galaxies · Physics 2017-01-09 Ekaterina V. Karukes , Paolo Salucci

We present a study of the shapes, orientations, and alignments of Galactic dark matter subhalos in the ``Via Lactea'' simulation of a Milky Way-size LCDM host halo. Whereas isolated dark matter halos tend to be prolate, subhalos are…

Astrophysics · Physics 2009-11-13 M. Kuhlen , J. Diemand , P. Madau

We have obtained ~100 pc resolution CO and ~60 pc resolution Halpha observations of the dwarf spiral galaxy NGC 4605. We use them to derive a high resolution rotation curve and study the central density profile of NGC 4605's dark matter…

Astrophysics · Physics 2009-11-07 Alberto D. Bolatto , Joshua D. Simon , Adam Leroy , Leo Blitz

Using high resolution DM simulations we study the shape of dark matter halos. Halos become more spherical with decreasing mass. This trend is even more pronounced for the inner part of the halo. Angular momentum and shape are correlated.…

Astrophysics · Physics 2009-11-11 Stefan Gottloeber , Victor Turchaninov

We obtain predictions for the properties of cold dark matter annihilation radiation using high resolution hydrodynamic zoom-in cosmological simulations of Milky Way-like galaxies (APOSTLE project) carried out as part of the "Evolution and…

Studies of dynamical stability (chaotic versus regular motion) in galactic dynamics often rely on static analytical models of the total gravitational potential. Potentials based upon self-consistent N-body simulations offer more realistic…

Astrophysics of Galaxies · Physics 2016-04-08 Rubens E. G. Machado , T. Manos