Related papers: On the non-thermal energy content of cosmic struct…
Non-thermal components are key ingredients for understanding clusters of galaxies. In the hierarchical model of structure formation, shocks and large-scale turbulence are unavoidable in the cluster formation processes. Understanding the…
We submit that non thermalized support for the outer intracluster medium in relaxed galaxy clusters is provided by turbulence, driven by inflows of intergalactic gas across the virial accretion shocks. We expect this component to increase…
There is compelling evidence that at least some clusters of galaxies are powerful sources of non-thermal radiation. In all cases where this radiation has been detected, a general trend is that high energy densities of cosmic rays and…
The existence of cosmic rays and weak magnetic fields in the intracluster volume has been well proven by deep radio observations of galaxy clusters. However a detailed physical characterization of the non-thermal component of large…
A diffuse non-thermal component has now been observed in massive merging clusters. To better characterise this component, and to extend analyses done for massive clusters down to a lower mass regime, we are conducting a statistical analysis…
I present a review of nonthermal processes in the large scale structure of the universe. After examining the properties of cosmological shock waves and their role as particle accelerators, I discuss the main observational facts, from radio…
Galaxy clusters grow by gas accretion, mostly from mergers of substructures, which release powerful shock waves into cosmic plasmas and convert a fraction of kinetic energy into thermal energy, amplification of magnetic fields and into the…
We present cosmological simulations of galaxy clusters, with focus on the cluster outskirts. We show that large-scale cosmic accretion and mergers produce significant internal gas motions and inhomogeneous gas distribution ("clumpiness") in…
(Abridged) The main purpose of this paper is to consider the contribution of all three non-thermal components to total mass measurements of galaxy clusters: cosmic rays, turbulence and magnetic pressures. To estimate the thermal pressure we…
Turbulent gas motion inside galaxy clusters provides a non-negligible non-thermal pressure support to the intracluster gas. If not corrected, it leads to a systematic bias in the estimation of cluster masses from X-ray and…
The nonthermal characteristics of starburst galaxies and galaxy clusters are reviewed and the perspectives for their observation in high energy gamma rays discussed. It is argued that starburst galaxies should have physically similar 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…
Shocks are a ubiquitous consequence of cosmic structure formation, and they play an essential role in heating galaxy cluster media. Virtually all of the gas in clusters has been processed by one or more shocks of at least moderate strength.…
We address the role of gamma-ray astronomy in the investigation of nonthermal processes in the large scale structure of the universe. Based on EGRET upper limits on nearby galaxy clusters (GCs) we constrain the acceleration efficiency of CR…
The nonthermal particle content of galaxy clusters should in part have a cosmological component generated during the early starburst phase of the member galaxies. This is reviewed in the framework of a simple cluster formation model…
Cosmological constraints from X-ray and microwave observations of galaxy clusters are subjected to systematic uncertainties. Non-thermal pressure support due to internal gas motions in galaxy clusters is one of the major sources of…
Radio observations prove the existence of relativistic particles and magnetic field associated with the intra-cluster-medium (ICM) through the presence of extended synchrotron emission in the form of radio halos and peripheral relics. This…
Recent observations of high energy (> 20 keV) X-ray emission in a few clusters of galaxies broaden our knowledge of physical phenomena in the intracluster space. This emission is likely to be nonthermal, probably resulting from Compton…
Recent statistical X-ray measurements of the intracluster medium (ICM) indicate that gas temperature profiles in the outskirts of galaxy clusters deviate from self-similar evolution. Using a mass-limited sample of galaxy clusters from…
As the nodes of the cosmic web, clusters of galaxies trace the large-scale distribution of matter in the Universe. They are thus privileged sites in which to investigate the complex physics of structure formation. However, the complete…