Related papers: Radio Plasma as a Cosmological Probe
In several merging clusters of galaxies so-called cluster radio relics have been observed. These are extended radio sources which do not seem to be associated with any radio galaxy. Two competing physical mechanisms to accelerate the radio…
The most spectacular aspect of cluster radio emission is represented by the large-scale diffuse radio sources, which cannot be obviously associated with any individual galaxy. These sources demonstrate the existence of relativistic…
We argue that clusters of galaxies have an intergalactic medium, which is permeated by strong magnetic fields and also has a contribution of pressure from cosmic rays. These two components of total pressure are probably highly time…
Multifiber optical spectroscopy has been performed on galaxies in the vicinity of strong, nearby radio galaxies. These radio galaxies were selected from the 3CR and B2 catalogs based on their exclusion from the Abell catalog, which is…
Relevant studies of the non-thermal components of the intracluster medium are performed at radio wavelengths. A number of clusters, indeed, exhibits cluster-wide diffuse radio emission, which is indication of the existence of large scale…
Radio relics are diffuse radio sources in galaxy clusters that are associated with merger shock waves. Detailed observations of radio relics in total intensity and in polarisation show complex structures on kiloparsec scales. The relation…
We discuss the possibility of using fast radio bursts (FRBs), if cosmological, as a viable cosmic probe. We find out that the contribution of the host galaxies to the detected dispersion measures can be inapparent for the FRBs not from…
We search for extended regions of radio emission not associated with Active Galactic Nuclei, known as 'relics', 'halos' and 'mini halo's, in a sample of 70 Abell clusters for which we have radio, optical and X-ray data. AGN can produce…
Although they were discovered more than 25 years ago, gamma-ray bursts are still a mystery. Even their characteristic distance is highly uncertain. All that we can be confident about is that they involve compact objects and relativistic…
This review discusses three ways in which radio galaxies and other high-redshift objects can give us information on the nature and statistics of cosmological inhomogeneities, and how they have evolved between high redshift and the present:…
The existence of intergalactic magnetic fields (IGMFs) is an open problem in cosmology and has never been unambiguously confirmed. High-energy gamma rays emitted by blazars are unique probes of cosmic magnetism, as their interactions with…
Galaxy clusters grow by mergers with other clusters and galaxy groups. These mergers create shocks within the intracluster medium (ICM). It is proposed that within the shocks particles can be accelerated to extreme energies. In the presence…
Galaxy clusters are unique laboratories to investigate turbulent fluid motions and large scale magnetic fields. Synchrotron radio halos at the center of merging galaxy clusters provide the most spectacular and direct evidence of the…
Relativistic plasmas in strong electromagnetic fields exhibit distinct properties compared to classical plasmas. In astrophysical environments, such as neutron stars, white dwarfs, AGNs, and shocks, relativistic plasmas are pervasive and…
Radio observations of galaxy clusters show that there are $\mu$G magnetic fields permeating the intra-cluster medium (ICM), but it is hard to accurately constrain the strength and structure of the magnetic fields without the help of…
It is well established that particle acceleration by shocks and turbulence in the intra-cluster medium can produce cluster-scale synchrotron emitting sources. However, the detailed physics of these particle acceleration processes is still…
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…
The interstellar medium (ISM) can be thought of as the galactic atmosphere which fills the space between stars. When clouds within the ISM collapse, stars are born. When the stars die, they return their matter to the surrounding gas.…
Clusters of galaxies are sites of acceleration of charged particles and sources of non-thermal radiation. We report on new constraints on the population of cosmic rays in the Intra Cluster Medium (ICM) obtained via radio observations of a…
It is proposed that radiation belts similar to the ones in the planetary magnetosphere can exist for a pulsar with a relatively long period and a strong magnetic field. In the belts located in the closed field line region near the light…