相关论文: The Dynamical State and Mass-Concentration Relatio…
A simple, observationally-motivated model is presented for understanding how halo masses, galaxy stellar masses, and star formation rates are related, and how these relations evolve with time. The relation between halo mass and galaxy…
We study the mass distribution of a sample of 24 X-ray bright Abell clusters through weak gravitational lensing. This method is independent of the dynamical state of the galaxy cluster. Hence, by comparing dynamical and lensing mass…
Hierarchical structure formation theory is based on the notion that mergers drive galaxy evolution, so a considerable framework of semi-analytic models and N-body simulations has been constructed to calculate how mergers transform a growing…
Cosmological models in which dark matter consists of cold elementary particles predict that the dark halo population should extend to masses many orders of magnitude below those at which galaxies can form. Here we report a cosmological…
Using a resimulation technique, we perform high-resolution cosmological simulations of dry mergers in a massive galaxy cluster identified in the Millennium Run. Our initial conditions include well resolved compound galaxy models consisting…
Clustering of dark matter halos has been shown to depend on halo properties beyond mass such as halo concentration, a phenomenon referred to as halo assembly bias. Standard halo occupation models (HOD) in large scale structure studies…
Like early-type galaxies, also nearby galaxy clusters define a Fundamental Plane, a luminosity-radius, and a luminosity-velocity dispersion relations, whose physical origin is still unclear. By means of high resolution N--body simulations…
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…
We present a numerical study of the evolution of galaxy clustering when galaxies flow passively from high redshift, respecting the continuity equation throughout. While passive flow is a special case of galaxy evolution, it allows a…
We investigate the growth of massive quiescent galaxies at $z<0.6$ based on the Sloan Digital Sky Survey and the Smithsonian Hectospec Lensing Survey---two magnitude limited spectroscopic surveys of high data quality and completeness. Our…
In the hierarchical formation model, galaxy clusters grow by accretion of smaller groups or isolated galaxies. During the infall into the centre of a cluster, the properties of accreted galaxies change. In particular, both observations and…
In this review, we describe our current understanding of cluster formation: from the general picture of collapse from initial density fluctuations in an expanding Universe to detailed simulations of cluster formation including the effects…
Properties of galaxies vary systematically with the mass of their parent dark matter halos. This basic galaxy - halo connection shows a fair amount of scatter whose origin is not fully understood. Here, we study how differences in the halo…
Understanding how galaxy properties are linked to the dark matter halos they reside in, and how they co-evolve is a powerful tool to constrain the processes related to galaxy formation. The stellar-to-halo mass relation (SHMR) and its…
Matter distribution around clusters is highly anisotropic from their being the nodes of the cosmic web. Clusters' shape and the number of filaments they are connected to, i.e., their connectivity, should reflect their level of anisotropic…
We use the Millennium Simulation database to compare how different versions of the Durham and Munich semi-analytical galaxy formation models populate dark matter haloes with galaxies. The models follow the same physical processes but differ…
A significant fraction of mass in the universe is believed to be in the form of dark matter (DM). Due to gravitational instability, the DM collapses hierarchically into DM halos. In this contribution we present a study of the formation and…
Observations from wide-field quasar surveys indicate that the quasar auto-correlation length increases dramatically from $z\approx2.5$ to $z\approx4$. This large clustering amplitude at $z\approx4$ has proven hard to interpret…
If dark matter has a large self-interaction scattering cross section, then interactions among dark-matter particles will drive galaxy and cluster halos to become spherical in their centers. Work in the past has used this effect to rule out…
Using a hydrodynamics plus N-body simulation of galaxy cluster formation within a large volume and mock Chandra X-ray observations, we study the form and evolution of the intrinsic scatter about the best-fit X-ray temperature-mass relation…