相关论文: Diffuse Cluster-wide Radio Halos
New radio and X-ray data are reported for the rich cluster Abell 2255. The cluster radio emission is characterized by the presence of a diffuse halo source, located at the cluster center, and a more peripheral ridge of radio emission which…
Low-frequency radio observations of galaxy clusters are the key to detecting the diffuse extended emission associated with them. The presence and properties of such radio sources in galaxy clusters reveal the existence of magnetic fields on…
We have developed a model in which the diffuse synchrotron emission from radio mini-halos, observed in some cooling flow clusters, is due to a relic population of relativistic electrons reaccelerated by MHD turbulence via Fermi-like…
Radio relics in galaxy clusters are extended synchrotron sources produced by cosmic-ray electrons in the $\mu$G magnetic field. Many relics are found in the cluster periphery and have a cluster-centric, narrow arc-like shape, which suggests…
Context. Radio halos are megaparsec-scale diffuse radio sources{ mostly} located at the centres of merging galaxy clusters. The common mechanism invoked to explain their origin is the re-acceleration of relativistic particles caused by…
Galaxy clusters with signs for a recent merger show in many cases extended diffuse radio features. This emission originates from relativistic electrons which suffer synchrotron losses due to the intra-cluster magnetic field. The mechanisms…
We use results from a constrained, cosmological MHD simulation of the Local Universe to predict radio halos and their evolution for a volume limited set of galaxy clusters and compare to current observations. The simulated magnetic field…
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…
A fraction of galaxy clusters host diffuse radio sources called radio halos, radio relics and mini-halos. We present the sample and first results from the Extended GMRT Radio Halo Survey (EGRHS)- an extension of the GMRT Radio Halo Survey…
Radio mini-halos are diffuse, steep-spectrum synchrotron sources associated with relaxed clusters of galaxies. Observations of some mini-halo sources indicate a correlation between the radio emission and the X-ray signature of gas sloshing,…
Recently, a number of new galaxy clusters have been detected by the ESA-Planck satellite, the South Pole Telescope and the Atacama Cosmology Telescope using the Sunyaev-Zeldovich effect. Several of the newly detected clusters are massive,…
Relativistic electrons, seen in the large diffuse radio halo of the Coma cluster of galaxies, should scatter background photons to higher energies. We calculate the inverse Compton contributions from the microwave background, from the local…
A781 belongs to a complex system characterized by extended X-ray emissions that may form part of line of clusters of galaxies along a filament. The aim of this work is to investigate the possible presence of extended, diffuse synchrotron…
Galaxy clusters have been found to host a range of diffuse, non-thermal emission components, generally with steep, power law spectra. In this work we report on the detection and follow-up of radio halos, relics, remnant radio galaxies, and…
We show an interesting correlation between the surface brightness and temperature structure of the relaxed clusters RXJ1720.1+2638 and MS1455.0+2232, hosting a pair of cold fronts, and their central core--halo radio source. We discuss the…
We report the detection of a diffuse radio halo source in the hottest known cluster of galaxies 1E0657-56 (RXJ0658-5557). The radio halo has a morphology similar to the X-ray emission from the hot intracluster medium. The presence of a…
A new model for the, so called, `cluster radio relics' is presented (Ensslin & Gopal-Krishna 2000). Fossil radio cocoons, resulting from the former activity of radio galaxies, should contain a low energy relativistic electron population and…
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…
Diffuse synchrotron emission in the form of radio halos and radio relics probe the existence of relativistic electrons and magnetic fields in galaxy clusters. These nonthermal components are generated from the dissipation of kinetic energy…
We report the detection of a diffuse radio halo source in the hottest known cluster of galaxies 1E0658-56 (RXJ0658-5557). The radio halo has a morphology similar to the X-ray emission from the hot intracluster medium. The detection of such…