Related papers: Radial orbit instability in dwarf dark matter halo…
We present stellar radial velocity data for the Draco dwarf spheroidal galaxy obtained using the AF2/WYFFOS instrument combination on the William Herschel Telescope. Our dataset consists of 186 member stars, 159 of which have good quality…
The existence of the Fundamental Plane (FP) imposes strong constraints on the structure and dynamics of elliptical galaxies, and thus contains important information on the processes of their formation and evolution. Here we focus on the…
We perform a series of high-resolution N-body simulations designed to examine the density profiles of dark matter halos. From 12 simulated halos ranging the mass of $2\times10^{12}\sim 5\times10^{14} h^{-1}{\rm M_\odot}$ (represented by…
Thanks to the ever increasing computational power and the development of more sophisticated algorithms, numerical N-body simulations are now uncovering several phenomenological relations between the physical properties of dark matter haloes…
We report a series of high-resolution N-body simulations designed to examine the internal physical properties of dark matter halos. A total of fifteen halos, each represented by $\sim 1$ million particles within the virial radius, have been…
We use the universal mass accretion history recently reported for simulations of halo formation in the cold dark matter model (CDM) to analyze the formation and growth of a single halo. We derive the time-dependent density profile three…
Spherical galaxy models with radially anisotropic velocity distributions merge faster than their isotropic counterparts. Here we investigate the effects of radially anisotropic haloes on the dynamics of disc galaxy encounters. We use stable…
We analyze the orbits of stars and dark matter particles in the halo of a disk galaxy formed in a cosmological hydrodynamical simulation. The halo is oblate within the inner ~20 kpc and triaxial beyond this radius. About 43% of orbits are…
We present distributions of the orbital parameters of dark matter substructures at the time of merging into their host halo. Accurate knowledge of the orbits of dark matter substructures is a crucial input to studies which aim to assess the…
We study the stability of trajectories near the disk plane of galaxy models with a triaxial dark matter halo component. We also examine the effect of weak discreteness noise, rapidly rotating bar perturbations and weak dissipation on these…
We describe an algorithm for constructing N-body realizations of equilibrium spherical systems. A general form for the mass density rho(r) is used, making it possible to represent most of the popular density profiles found in the…
We examine the bar instability in galactic models with an exponential disk and a cuspy dark matter (DM) halo with a Navarro-Frenk-White (NFW) cosmological density profile. We construct equilibrium models from a 3-integral composite…
Dark matter haloes in cosmological N-body simulations are affected by processes such as mergers, accretion and the gravitational interaction with baryonic matter. Typically the analysis of dark matter haloes is performed in spherical or…
We confirm and extend the recent finding that the central surface density r_0*rho_0 galaxy dark matter halos, where r_0 and rho_0 are the halo core radius and central density, is nearly constant and independent of galaxy luminosity. Based…
The standard cold dark matter (CDM) model has recently been challenged by the claim that dwarf galaxies have dark matter halos with constant density cores. Consequently, numerous alternative dark matter candidates have recently been…
In the past years a wealth of observations allowed to unravel the structural properties of the Dark Matter Halos around spirals. First, their rotation curves follow an Universal profile (URC) that can be described in terms of an exponential…
We investigate the regular or chaotic nature of orbits of stars moving in the meridional plane (R,z) of an axially symmetric galactic model with a dense, massive spherical nucleus and a dark matter halo component. In particular, we study…
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…
Using realistic cosmological simulations of Milky Way sized haloes, we study their dynamical state and the accuracy of inferring their mass profiles with steady-state models of dynamical tracers. We use a new method that describes the…
Context. The cusp-core discrepancy is one of the major problems in astrophysics. It results from comparing the observed mass distribution of galaxies with the predictions of Cold Dark Matter simulations. The latter predict a cuspy density…