Related papers: Dark Matter Halos from the Inside Out
Cosmological N--body simulations have revealed a remarkable similarity in the structure of dark matter halos formed in hierarchically clustering universes. Regardless of halo mass, cosmological parameters, and power spectrum of initial…
The role of baryonic physics, star formation, and stellar feedback, in shaping the galaxies and their host halos is an evolving topic. The dark matter aspects are illustrated in this work by showing distribution features in a…
The dark matter halo sparsity provides a direct observational proxy of the halo mass profile, characterizing halos in terms of the ratio of masses within radii which enclose two different overdensities. Previous numerical simulation…
The structure and dynamics of dark matter halos, as predicted by the hierarchical clustering scenario, are at odds with the properties inferred from the observations at galactic scales. My Thesis addresses this problem by taking an…
We have identified over 2000 well resolved cluster halos, and also their associated bound subhalos, from the output of a 1024^3 particle cosmological N-body simulation (of box size 320 h^-1 Mpc and softening length 3.2 h^-1 kpc). This has…
High-resolution N-body simulations of hierarchical cosmologies have shown that the density and velocity dispersion profiles of dark-matter haloes display well-definite universal forms whose origin remains unknown. In the present paper, we…
We provide new constraints on the connection between galaxies in the local universe, identified by the Sloan Digital Sky Survey (SDSS), and dark matter halos and their constituent substructures in the $\Lambda$CDM model using WMAP7…
We use the Millennium Simulation, a large, high resolution N-body simulation of the evolution of structure in a LambdaCDM cosmology, to study the properties and fate of substructures within a large sample of dark matter haloes. We find that…
Individual dark matter halos in cosmological simulations vary widely in their detailed structural properties such as shape, rotation, substructure and degree of internal relaxation. Recent non-parametric (principal component) analyses…
We investigate the structure of the dark matter halo formed in the cold dark matter scenario using $N$-body simulations. We simulated 12 halos with the mass of $6.6\times 10^{11}M_{\odot}$ to $8.0\times 10^{14}M_{\odot}$. In almost all…
We consider the possibility that the dark matter in the halos of galaxies may be in the form of clusters of \macho s within which are embedded cold, dense gas clouds. Microlensing experiments have found evidence that the Galactic halo…
Gravitational lensing has now become a popular tool to measure the mass distribution of structures in the Universe on various scales. Here we focus on the study of galaxy's scale dark matter halos with galaxy-galaxy lensing techniques:…
The condensation of gas and stars in the inner regions of dark matter halos leads to a more concentrated dark matter distribution. While this effect is based on simple gravitational physics, the question of its validity in hierarchical…
In the cold dark matter scenario, the smallest dark matter halos may be earth mass or smaller. These microhalos would be the densest dark matter objects in the Universe, making their accurate characterization important for astrophysical…
The characteristic prediction of the Cold Dark Matter (CDM) model of cosmological structure formation is that the Universe should contain a wealth of small-scale structure -- low-mass dark matter haloes and subhaloes. However, galaxy…
Clusters of galaxies are studied from a theoretical point of view, comparing with observational results whenever possible. The problem is approached both analytically as well as by means of high-resoultion numerical simulations. The dark…
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 N-body/gasdynamical LambdaCDM cosmological simulations to examine the effect of the assembly of a central galaxy on the shape and mass profile of its dark halo. Two series of simulations are compared; one that follows only the…
Much recent discussion about dark matter has been centered on two seemingly independent problems: the abundance of substructure in dark matter halos, and the cuspiness of the halos' inner density profile. We explore possible connections…
The Cold Dark Matter theory of gravitationally-driven hierarchical structure formation has earned its status as a paradigm by explaining the distribution of matter over large spans of cosmic distance and time. However, its central tenet,…