相关论文: Dependence of Halo Properties on Interaction Histo…

The effects of merging histories of proto-objects on the angular momentum distributions of the present-time dark matter haloes are analysed. An analytical approach to the analysis of the angular momentum distributions assumes that the…

We perform collisionless N-body simulations of 1:1 galaxy mergers, using models which include a galaxy halo, disc and bulge, focusing on the behaviour of the halo component. The galaxy models are constructed without recourse to a Maxwellian…

In an earlier paper we quantified the mean merger rate of dark matter haloes as a function of redshift z, descendant halo mass M0, and progenitor halo mass ratio xi using the Millennium simulation of the LCDM cosmology. Here we broaden that…

We evaluate the accuracy of semi-analytic merger-trees by comparing them with the merging histories of dark-matter halos in N-body simulations, focusing on the joint distribution of the number of progenitors and their masses. We first…

We have made a detailed comparison of the results of large N-body simulations with the analytical description of the merging histories of dark matter halos presented in Lacey & Cole 1993, which is based on an extension of the Press-…

Galaxy mergers are a fundamental part of galaxy evolution. To study the resulting mass distributions of different kinds of galaxy mergers, we present a simulation suite of 36 high-resolution isolated merger simulations, exploring a wide…

A common approach in semi-analytic modeling of galaxy formation is to construct Monte Carlo realizations of merger histories of dark matter halos whose masses are sampled from a halo mass function. Both the mass function itself, and the…

We develop a hybrid galaxy formation model which uses outputs from an N-body simulation to follow the merger histories (or ``merger trees'') of dark matter halos and treats baryonic processes, such as the cooling of gas within halos and…

We present new results on the angular momentum evolution of dark matter halos. Halos, from N-body simulations, are classified according to their mass growth histories into two categories: the accretion category contains halos whose mass has…

We construct merger trees from the largest database of dark matter haloes to date provided by the Millennium simulation to quantify the merger rates of haloes over a broad range of descendant halo mass (1e12 < M0 < 1e15 Msun), progenitor…

We introduce and apply a new approach to probe the response of galactic stellar haloes to the interplay between cosmological merger histories and galaxy formation physics. We perform dark matter-only, zoomed simulations of two Milky…

We extend the random-walk model of Vitvitska et al. for predicting the spins of dark matter halos from their merger histories. Using updated merger rates, orbital parameter distributions, and N-body constraints we show that this model can…

According to the hierarchical scenario, galaxies form via merging and accretion of small objects. Using N-body simulations, we study the frequency of merging events in the history of the halos. We find that at z<~2 the merging rate of the…

A modified version of the extended Press-Schechter model for the growth of dark-matter haloes was introduced in two previous papers with the aim at explaining the mass-density relation shown by haloes in high-resolution cosmological…

Galaxy merger timescales are crucial for understanding and modeling galaxy formation in our hierarchically structured Universe. However, previous studies have reported widely varying dependencies of merger timescales on initial orbital…

We model the acquisition of spin by dark-matter halos in semi-analytic merger trees. We explore two different algorithms; one in which halo spin is acquired from the orbital angular momentum of merging satellites, and another in which halo…

We analyze N-body simulations of halo mergers to investigate the mechanisms responsible for driving mixing in phase-space and the evolution to dynamical equilibrium. We focus on mixing in energy and angular momentum and show that mixing…

The structural properties of individual dark matter haloes, including shape, spin, concentration, and substructure, are linked to the halo's growth history, but the exact connection between the two is unclear. One open question, in…

We study merger histories of dark-matter haloes in a suite of N-body simulations that span different cosmological models. The simulated cases include the up-to-date WMAP5 cosmology and other test cases based on the Einstein-deSitter…

Several lines of evidence suggest that as dark matter haloes grow their scale radius increases, and that the density in their central region drops. Major mergers seem an obvious mechanism to explain both these phenomena, and the resulting…