相关论文: The baseline intracluster entropy profile from gra…

The X-ray properties of a relaxed cluster of galaxies are determined primarily by its gravitational potential well and the entropy distribution of its intracluster gas. That entropy distribution reflects both the accretion history of the…

We investigated the numerical and physical reasons leading to a flat distribution of low gas entropy in the core region of galaxy clusters, as commonly found in grid cosmological simulations. To this end, we run a set of 30 high resolution…

[Abridged] The entropy distribution of the intracluster gas reflects both accretion history of the gas and processes of feedback which provide a further non-gravitational energy besides the potential one. In this work, we study the profiles…

Recent high-resolution cosmological hydrodynamic simulations run with a variety of codes systematically predict large amounts of entropy in the intra-cluster medium at low redshift, leading to flat entropy profiles and a suppressed…

Studies of the X-ray surface brightness profiles of clusters, coupled with theoretical considerations, suggest that the breaking of self-similarity in the hot gas results from an `entropy floor', established by some heating process, which…

Some observations such as those presented in Walker et al. show that the observed entropy profiles of the intra-cluster medium (ICM) deviate from the power-law prediction of adiabatic simulations. This implies that non-gravitational…

We present the first results of our study of a sample of 101 X-ray galaxy groups and clusters, which is volume-limited in each of three X-ray luminosity bins. The aim of this work is to study the properties of the innermost ICM in the cores…

Recently, Suzaku has produced temperature and entropy profiles, along with profiles of gas density, gas fraction, and mass, for multiple galaxy clusters out to ~r_200 (~= virial radius). In this paper, we compare these novel X-ray…

We present a set of cluster models that link the present-day properties of clusters to the processes that govern galaxy formation. These models treat the entropy distribution of the intracluster medium as its most fundamental property.…

A semi-analytic model of cluster cooling flows is presented. The model assumes that episodic nuclear activity followed by radiative cooling without mass-dropout cycles the cluster gas between a relatively homogeneous, nearly isothermal…

The non-gravitational energy feedback is of crucial importance in modeling/simulating clusters to be used as cosmological probes. AGNs are, arguably, of primary importance in injecting energy in the cluster cores. We make the first estimate…

We present results obtained from a set of cosmological hydrodynamic simulations of galaxy clusters, aimed at comparing predictions with observational data on the diversity between cool-core (CC) and non-cool-core (NCC) clusters. Our…

High resolution X-ray observations indicate that the entropy profiles in the central regions of some massive cooling flow clusters are well approximated by powerlaws. McCarthy and coworkers recently accounted for this trend with an analytic…

We study the X-ray cluster gas density distribution in hydrostatic equilibrium using the universal temperature profile obtained from recent simulations involving only gravitational processes. If this temperature profile is an indicator of…

The intergalactic gas in groups and clusters of galaxies bears the indelible stamp of galaxy formation. We present a comparison between observations and simple theoretical models indicating that radiative cooling governs the entropy scale…

Non-gravitational feedback affects the nature of the intra-cluster medium (ICM). X-ray cooling of the ICM and in situ energy feedback from AGN's and SNe as well as {\it preheating} of the gas at epochs preceding the formation of clusters…

The entropy of the intracluster medium at large radii has been shown recently to deviate from the self-similar scaling with temperature. Using N-body/hydrodynamic simulations of the LCDM cosmology, we demonstrate that this deviation is…

We present detailed comparisons of the intracluster medium (ICM) in cosmological Eulerian cluster simulations with deep Chandra observations of nearby relaxed clusters. To assess the impact of galaxy formation, we compare two sets of…

We examine profiles and scaling properties of the entropy of the intergalactic gas in a sample of 66 virialized systems, ranging in mass from single elliptical galaxies to rich clusters, for which we have resolved X-ray temperature…

Using a set of hydrodynamical simulations of 9 galaxy clusters with masses in the range 1.5 10^{14} M_sun < M_vir < 3.4 10^{15} M_sun, we have studied the density, temperature and X-ray surface brightness profiles of the intracluster medium…