相关论文: Gas rich and gas poor structures through the strea…
We study the effect of baryons on the abundance of structures and substructures in a Lambda-CDM cosmology, using a pair of high resolution cosmological simulations from the GIMIC project. Both simulations use identical initial conditions,…
Simulations of tidal streams show that close encounters with dark matter subhalos induce density gaps and distortions in on-sky path along the streams. Accordingly, observing disrupted streams in the Galactic halo would substantiate the…
We investigate the evolution of density perturbations in dark matter, including the new combined effects of finite number density and non-zero velocity dispersion. Using a truncated BBGKY hierarchy, we derive analytical expressions for the…
The halo mass function, dn/dM, predicted by hierarchical clustering models can be measured indirectly using dynamical probes like the distribution of gravitational lens image separations, dn/dDelta-theta, or halo circular velocities, dn/d…
Baryonic physics is anticipated to be a major source of systematic uncertainty in current and future large-scale cosmological surveys. We investigate how baryonic effects on halo density profiles vary with secondary halo properties at fixed…
The baryonic discs of galaxies are believed to alter the shapes of the dark matter haloes in which they reside. We perform a set of hydrodynamical N-body simulations of disc galaxies with triaxial dark matter haloes, using elliptical discs…
The spatial distribution of matter in clusters of galaxies is mainly determined by the dominant dark matter component, however, physical processes involving baryonic matter are able to modify it significantly. We analyse a set of 500 pc…
Gas rich sub-galactic halos with mass Mt <= 10^7.5 Msun, while incapable of forming stars due to lack of adequate coolants, contain a large fraction of baryonic mass at cosmological reionization. We show that the reionization of the…
Inverse mass cascade is a key feature of the intermediate statistically steady state for self-gravitating collisionless dark matter flow (SG-CFD). This paper focus on effects of mass cascade on halo energy, momentum, dispersion, size, and…
[Abridged] We present an analysis of the relation between the masses of cluster- and group-sized halos, extracted from $\Lambda$CDM cosmological N-body and hydrodynamic simulations, and their velocity dispersions, at different redshifts…
We study the local dark matter velocity distribution in simulated Milky Way-mass galaxies, generated at high resolution with both dark matter and baryons. We find that the dark matter in the Solar neighborhood is influenced appreciably by…
We investigate the impact of dynamical streams and substructure on estimates of the local escape speed and total mass of Milky Way-mass galaxies from modelling the high velocity tail of local halo stars. We use a suite of high-resolution,…
Gravitational encounters between small-scale dark matter substructure and cold stellar streams in the Milky Way halo lead to density perturbations in the latter, making streams an effective probe for detecting dark matter substructure. The…
Several studies have shown the influence of the relative streaming velocity (SV) between baryons and dark matter on the formation of structures. For the first time, we constrain the local value of the SV in which the Milky Way was formed.…
In cold dark matter cosmological models, structures form and grow by merging of smaller units. Numerical simulations have shown that such merging is incomplete; the inner cores of halos survive and orbit as "subhalos" within their hosts.…
Dark matter sub-halos that pass near or through a thin tidal star stream locally increase its velocity dispersion. Subsequent orbital evolution further increases the velocity dispersion and stream width, lowering the surface density of a…
Cosmological hydrodynamical simulations as well as observations indicate that spiral galaxies are comprised of five different components: dark matter halo, stellar disc, stellar bulge, gaseous disc and gaseous halo. While the first four…
We study the cosmological evolution of baryons in universes with and without primordial non-Gaussianities via (large scale) N-body/hydrodynamical simulations, including gas cooling, star formation, stellar evolution, chemical enrichment…
Feedback processes from baryons are expected to strongly affect weak-lensing observables of current and future cosmological surveys. In this paper we present a new parametrisation of halo profiles based on gas, stellar, and dark matter…
We investigate the impact of thermal velocities in N-body simulations of structure formation in warm dark matter models. Adopting the commonly used approach of adding thermal velocities, randomly selected from a Fermi-Dirac distribution, to…