Related papers: Gravitational diffusion in the intra-cluster mediu…
There is increasing evidence that some heating mechanism in addition to gravitational shock heating has been important for the hot gas inside clusters and groups of galaxies, as indicated by their observed X-ray scaling properties. While…
Quasar absorption lines now permit a direct probe of deuterium abundances in primordial material, with the best current estimate $ (D/H)=1.9\pm 0.4 \times 10^{-4}$. If this is the universal primordial abundance $(D/H)_p$, Standard Big Bang…
Concentration is one of the key dark matter halo properties that could drive the scatter in the stellar-to-halo mass relation of massive clusters. We derive robust photometric stellar masses for a sample of brightest central galaxies (BCGs)…
The physics of the intracluster medium, in particular the values for the thermal conductivity and the viscosity are largely unknown and subject to an ongoing debate. Here, we study the effect of viscosity on the thermal state of the…
By combining galaxy tracers from high-resolution N-body and hydrodynamical simulations, we present a consistent picture of the behaviour of galaxy velocities in massive clusters. In haloes above ~ 10^14 Msun, the brightest satellite…
Assuming that there exists a species of heavy sterile neutrinos($m_{\nu}>1$ keV) and their decays can serve as a heating source of the hot gas in galaxy clusters, we study how the observational constraints on cooling flow limit the mass of…
The thermodynamics of the diffuse, X-ray emitting gas in clusters of galaxies is linked to the entropy level of the intra cluster medium. In particular, models that successfully reproduce the properties of local X-ray clusters and groups…
Observations of gravitational lensing indicate that the mass distribution in clusters of galaxies (where most of the mass is dark matter) is highly peaked towards the center, while X-ray observations imply that the gas is more extended. The…
This paper discusses low mass, metal poor stars, presenting new evolutionary computations which take into account the inward diffusion of both He and heavy elements during the H burning phase. The investigation has been extended to He…
From X-ray observations of galaxy clusters one derives the mass of the intracluster medium along with its chemical composition. Optical/infrared observations are used to estimate the mass of the stellar components of galaxies, along with…
Recent X-ray and optical observations of the Perseus cluster indicate that the viscous and conductive dissipation of sound waves is the mechanism responsible for heating the intracluster medium and thus balancing radiative cooling of…
Our current knowledge of the thermodynamic properties of galaxy clusters comes primarily from detailed studies of clusters selected by their minority components: hot baryons. Most of these studies select the clusters using the component…
We aim to determine the intrinsic variety, at a given mass, of the properties of the intracluster medium in clusters of galaxies. This requires a cluster sample selected independently of the intracluster medium content for which reliable…
Intercluster medium is expected to be turbulent with turbulence being superAlfvenic at large scales. Magnetic fields substantially modify the turbulent cascade when the turbulence reaches the scales at which the fluctuation velocity gets…
Recent X-ray observations of clusters of galaxies have shown that the entropy of the intracluster medium (ICM), even at radii as large as half the virial radius, is higher than that expected from gravitational processes alone. This is…
Using CCD detectors onboard the forthcoming X-ray observatories Chandra and XMM, it is possible to devise a measurement of the absolute density of heavy elements in the hypothetical warm gas filling intercluster space. This gas may be the…
We investigate the origin of the variation of the gas mass fraction in the core of galaxy clusters, which was indicated by our work on the X-ray fundamental plane. The adopted model supposes that the gas distribution characterized by the…
We calculate X-ray properties of present-day galaxy clusters from hydrodynamical cosmological simulations of the LCDM cosmology and compare these with recent X-ray observations. Results from three simulations are presented, each of which…
The gas in the cores of many clusters and groups of galaxies has a short radiative cooling time. Energy from the central black hole is observed to flow into this gas by means of jets, bubbles and sound waves. Cooling is thus offset by…
The hot gas permeating galaxy clusters-the intracluster medium (ICM)-is a key tracer of their assembly history and internal dynamics. Understanding the motion of this gas provides critical insight into processes such as mergers, turbulence,…