相关论文: Cosmic rays in galaxy clusters and their non-therm…
The nonthermal radiation observed from a handfull of clusters of galaxies (CG) is the proof that particle acceleration occurs in the intracluster medium (ICM). It is often believed that shock surfaces associated with either mergers of CG,…
Accelerated particles are ubiquitous in the Cosmos and play a fundamental role in many processes governing the evolution of the Universe at all scales, from the sub-AU ones relevant for the formation and evolution of stars and planets to…
Radio galaxies in clusters of galaxies are prominent reservoirs of magnetic fields and of non-thermal particles, which get mixed with the intracluster medium. We review the observational and theoretical knowledge of the role of these…
Cooling flows are regions where the importance of non-thermal intra-cluster medium components such as magnetic fields and cosmic rays may be strongest within a galaxy cluster. They are also regions where such components are best detectable…
The thermal plasma of galaxy clusters lost most of its information on how structure formation proceeded as a result of dissipative processes. In contrast, non-equilibrium distributions of cosmic rays (CR) preserve the information about…
The most important evidences for non-thermal phenomena in galaxy clusters comes from the spectacular synchrotron radio emission diffused over Mpc scale observed in a growing number of massive clusters. A promising possibility to explain…
We discuss the origin of thermal and non-thermal phenomena in galaxy clusters. Specifically, we present some expectations for the non-thermal emission (from radio to gamma ray wavelenghts) expected in a model in which secondary electrons…
We study non-thermal emissions from cool cores in galaxy clusters. We adopted a recent model, in which cosmic-rays (CRs) prevail in the cores and stably heat them through CR streaming. The non-thermal emissions come from the interaction…
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…
Gamma-ray astronomy will play a crucial role in the investigation of nonthermal processes in the large scale structure of the universe. Particularly, galaxy clusters (GC) observations at this photon energy will help us understand the origin…
The recent evidences of the presence of magnetic fields and relativistic particles in galaxy clusters are reviewed. The existence of microG-level magnetic fields in cluster atmospheres appears well established from the detection of diffuse…
The nature of cosmic rays (CRs) and cosmic ray transport in galaxy clusters is probed by a number of observations. Radio observations reveal the synchrotron radiation of cosmic ray electrons (CRe) spiraling around cluster magnetic fields.…
The study of diffuse radio sources is essential to our knowledge of the physical conditions in clusters of galaxies and of the role that large scale magnetic fields play in the propagation of the relativistic particles in the intracluster…
Observations of large-scale radio emissions prove the existence of shock accelerated cosmic-ray electrons in galaxy clusters, while the lack of detected $\gamma$-rays limits the acceleration of cosmic-ray protons in galaxy clusters. This…
The search for gamma radiation in clusters of galaxies represents a precious tool to investigate the history of these large scale structures. Clusters or sources within them accelerate cosmic rays, as demonstrated by the detection of radio…
Deep radio observations of galaxy clusters have revealed the existence of diffuse radio sources ("halos" and "relics") related to the presence of relativistic electrons and weak magnetic fields in the intracluster volume. I will outline our…
Radio observations discovered large scale non thermal sources in the central Mpc regions of dynamically disturbed galaxy clusters (radio halos). The morphological and spectral properties of these sources suggest that the emitting electrons…
Understanding the physical mechanisms that control galaxy formation is a fundamental challenge in contemporary astrophysics. Recent advances in the field of astrophysical feedback strongly suggest that cosmic rays (CRs) may be crucially…
An important area of study of cosmic magnetic fields is on the largest scales, those of clusters of galaxies. In the last decade it has become clear that the intra-cluster medium (ICM) in clusters of galaxies is magnetized and that magnetic…
Galaxy clusters host the largest particle accelerators in the Universe: Shock waves in the intracluster medium (ICM), a hot and ionised plasma, that accelerate particles to high energies. Radio observations pick up synchrotron emission in…