相关论文: Toward Understanding Environmental Effects in SDSS…
We analyze with hydrodynamical simulations the evolution of galaxy clusters in a cosmological environment. Power ratios (Buote \& Tsai 1995) are used to quantitatively relate cluster morphologies to their dynamical states. The simulated…
According to the cosmological principle, galaxy cluster sizes and cluster densities, when averaged over sufficiently large volumes of space, are expected to be constant everywhere, except for a slow variation with look-back time (redshift).…
The ``MORPHS'' group has completed the cataloging, parameterization, and morphological classification of ~2000 galaxies in 10 rich clusters from 0.36 < z < 0.56. From a weak lensing analysis using these data, which compares the X-ray…
We use a volume-limited galaxy sample from the SDSS Data Release 7 to explore the dependence of galactic conformity on the large-scale environment, measured on $\sim$ 4 Mpc scales. We find that the star formation activity of neighbour…
Understanding the formation and evolution of high mass star clusters requires comparisons between theoretical and observational data to be made. Unfortunately, while the full phase space of simulated regions is available, often only partial…
By virtue of their high galaxy space densities and their large spatial separations, clusters are efficient and accurate tracers of the large-scale density and velocity fields. Substantial progress has been made over the past decade in the…
Tidal forces acting on galaxies in clusters lead to a strong dynamical evolution. In order to quantify the amount of evolution, I run self-consistent N-body simulations of disk galaxies for a variety of models in the hierarchically forming…
We study the relations between the multimodality of galaxy clusters drawn from the SDSS DR8 and the environment where they reside. We find that multimodal clusters reside in higher density environment than unimodal clusters. We determine…
As the densest galaxy environments in the universe, clusters are vital to our understanding of the role that environment plays in galaxy formation and evolution. Unfortunately, the evolution of high-redshift cluster galaxies is poorly…
We probe the evolution of globular clusters that could form in giant molecular clouds within high-redshift galaxies. Numerical simulations demonstrate that the large and dense enough gas clouds assemble naturally in current hierarchical…
We have studied the population-density relation in very sparse environments, from poor clusters to isolated galaxies, and we find that early-type galaxies with a young stellar population are preferably found in the lowest density…
The cluster correlation function and its richness dependence are determined from 1108 clusters of galaxies -- the largest sample of clusters studied so far -- found in 379 deg^2 of Sloan Digital Sky Survey early data. The results are…
Deep images of 10 early-type galaxies in low-density environments have been obtained with the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope. The global properties of the globular cluster (GC) systems of the galaxies have…
(abridged) The old Star Cluster (SC) systems surrounding any sofar investigated galaxy represent a powerful tool for the understanding of the cosmological evolution of their host galaxies. Phases of enhanced cluster formation can be…
We determine the shape, multiplicity, size, and radial structure of superclusters in the LambdaCDM concordance cosmology from z = 0 to z = 2. Superclusters are defined as clusters of clusters in our large-scale cosmological simulation. We…
We study the properties of dark matter haloes of a LCDM model in different environments. Using the distance of the 5th nearest neighbour as an environmental density indicator, we show that haloes in a high density environment are more…
We use photometric redshifts derived from new $u$-band through 4.5$\mu$m Spitzer IRAC photometry in the 4.8\,deg$^2$ of the XMM-LSS field to construct surface density maps in the redshift range 0.1-1.5. Our density maps show evidence for…
Most stars are born in the crowded environments of gradually forming star clusters. Dynamical interactions between close-passing stars and the evolving UV radiation fields from proximate massive stars are expected to sculpt the…
The cluster environment is the site of important transformations in galaxies at a relatively recent cosmological epoch: the galactic morphological types and star formation activity have evolved significantly during the last few Gyrs. How is…
We analyze systematic effects in the determination of the galaxy luminosity function in clusters using a deep mock catalogue constructed from a numerical simulation of a hierarchical universe. The results indicate a strong tendency to…