相关论文: Virialization of Galaxy Clusters and Beyond
We present a general statistical framework for describing the effect of sample variance in the number counts of virialized objects and examine its effect on cosmological parameter estimation. Specifically, we consider effects of sample…
We present a study of multiwavelength X-ray and weak lensing scaling relations for a sample of 50 clusters of galaxies. Our analysis combines Chandra and XMM-Newton data using an energy-dependent cross-calibration. After considering a…
Clusters of galaxies are the most massive virialized structures in the Universe. The microphysical properties of the intracluster plasma can affect dynamical processes over an enormous range: from the feedback of active galactic nuclei to…
Using an ensemble of high resolution 2D numerical simulations, we explore the scaling properties of cosmological density fluctuations in the non-linear regime. We study the scaling behaviour of the usual $N$--point volume-averaged…
We present results of a study of the virial state of high redshift dark matter haloes in an N-body simulation. We find that the majority of collapsed, bound haloes are not virialized at any redshift slice in our study ($z=15-6$) and have…
We use cosmological hydrodynamical simulations to study the effect of screened modified gravity models on the mass estimates of galaxy clusters. In particular, we focus on two novel aspects: (i) we study modified gravity models in which…
Dynamically relaxed galaxy clusters have long played a role in galaxy cluster studies because it is thought their properties can be reconstructed more precisely and with less systematics. As relaxed clusters are desirable, there exist a…
Fractal structures and non-Gaussian velocity distributions are characteristic properties commonly observed in virialized self-gravitating systems such as galaxies or interstellar molecular clouds. We study the origin of these properties…
We used archival ROSAT observations to investigate the X-ray surface brightness profiles of a sample of 26 clusters in the redshift range (0.04-0.06). For 15 of these clusters accurate temperature (kT>3.5 keV) were available from the…
We investigate the clustering properties and close neighbour counts for galaxies with different types of bulges and stellar masses. We select samples of "classical" and "pseudo" bulges, as well as "bulge-less" disk galaxies, based on the…
We measure the thermodynamic properties of cluster outer regions to provide constraints on the processes that rule the formation of large scale structures. We derived the thermodynamic properties of the intracluster gas (temperature,…
Evidence is presented for a recent evolution of the relaxation processes in clusters of galaxies, using large optical and X-ray cluster samples. The criteria of the cluster relaxation used are the cluster ellipticity, the ICM temperature…
The diversity of galaxy morphologies and their relations with galaxy and halo properties is fundamental to understanding galaxy formation. Cosmological simulations of representative volumes can help disentangle the origin of observed…
Gas masses tightly correlate with the virial masses of galaxy clusters, allowing for a precise determination of cosmological parameters by means of large-scale X-ray surveys. However, according to recent Suzaku X-ray measurements, gas mass…
We have used recent X-ray and optical data in order to impose some constraints on the cosmology and cluster scaling relations. Generically two kind of hypotheses define our model. First we consider that the cluster population is well…
We present the analysis of baryonic and non-baryonic matter distribution in a sample of ten nearby clusters ($0.03<z<0.09$) with temperatures between 4.7 and 9.4 keV. These galaxy clusters have been studied in detail using X-ray data and…
Studies of disordered heterogeneous media and galaxy cosmology share a common goal: analyzing the distribution of particles at `microscales' to predict physical properties at `macroscales', whether for a liquid, composite material, or…
Galaxy clusters are unique laboratories for studying astrophysical processes and their impact on gas kinematics. Despite their importance, the full complexity of gas motion within and around clusters remains poorly known. This paper is part…
We aim at investigating potential biases in lensing and X-ray methods to measure the cluster mass profiles. We do so by performing realistic simulations of lensing and X-ray observations that are subsequently analyzed using observational…
Anomalous coarsening in far-from equilibrium one-dimensional systems is investigated by simulation and analytic techniques. The minimal hard core particle (exclusion) models contain mechanisms of aggregated particle diffusion, with rates…