Related papers: Scalelengths in Dark Matter Halos
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…
Dark-matter halos are the scaffolding around which galaxies and clusters are built. They form when the gravitational instability of primordial density fluctuations causes regions which are denser than average to slow their cosmic expansion,…
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…
This work investigates a set of cosmological collisionless N-body simulations with featured power spectra of initial perturbations in the context of the core-cusp and satellites problems. On the studied power spectra some scales of…
The gravitationally-driven evolution of cold dark matter dominates the formation of structure in the Universe over a wide range of length scales. While the longest scales can be treated by perturbation theory, a fully quantitative…
We test the long-term kinematical stability of a Galactic stellar halo model, due to Kafle, et al. (2012), who study the kinematics of approximately 5000 blue horizontal branch (BHB) stars in the Sloan Digital Sky Survey (SDSS). The…
We investigate the intrinsic alignments of dark halo substructures with their host halo major-axis orientations both analytically and numerically. Analytically, we derive the probability density distribution of the angles between the minor…
We summarize recent developments in the study of the origin of halo spin profiles and preliminary implications on disk formation. The specific angular-momentum distributions within halos in N-body simulations match a universal shape, M(<j)…
Adaptive SPH and N-body simulations were carried out to study the collapse and evolution of dark matter halos that result from the gravitational instability and fragmentation of cosmological pancakes. Such halos resemble those formed by…
Pulsar halos are produced by electrons and positrons diffusing in the interstellar medium around their parent pulsar wind nebulae. Recent observations by HAWC and LHAASO have revealed asymmetric morphologies in the halos surrounding Geminga…
We argue that a universal density profile for dark matter halos arises as a natural consequence of hierarchical structure formation. It is a fixed point in the process of repeated mergers. We present analytic and numerical arguments for the…
Dark matter halos can be defined as smooth distributions of dark matter placed in a non-smooth cosmic web structure. This definition of halos demands a precise definition of smoothness and a characterization of the manner in which the…
We investigate the connection between collisionless equilibria and the phase-space relation between density $\rho$ and velocity dispersion $\sigma$ found in simulations of dark matter halo formation, $F=\psd \propto r^{-\alpha}$.…
The dissipative infall of gas during the formation of a galaxy modifies the density profile and shape of the dark halo. Gas dissipates energy radiatively and sinks to the center of the dark halo forming the luminous part of a galaxy. The…
The evolution of linear initial conditions present in the early universe into extended halos of dark matter at late times can be computed using cosmological simulations. However, a theoretical understanding of this complex process remains…
We develop a model for the growth of dark matter halos and use it to study their evolved density profiles. In this model, halos are spherical and form by quiescent accretion of matter in clumps, called satellites. The halo mass as a…
The formation of galaxy clusters in hierarchically clustering universes is investigated by means of high resolution N-body simulations. The simulations are performed using a newly developed multi-mass scheme which combines a PM code with a…
We examine the properties of dark matter halos within a rich galaxy cluster using a high resolution simulation that captures the cosmological context of a cold dark matter universe. The mass and force resolution permit the resolution of 150…
The Cold Dark Matter paradigm successfully explains many phenomena on scales larger than galaxies, but seems to predict galaxy halos which are more centrally concentrated and have a lumpier substructure than observed. Endowing cosmic dark…
We use a high-resolution N-body simulation to study how the influence of large-scale structure in and around clusters causes correlated signals in different physical probes and discuss some implications this has for multi-physics probes of…