相关论文: New scaling relations in cluster radio halos and t…
In this work, we present a study of the central regions of cool-core clusters hosting radio mini-halos, which are di use synchrotron sources extended on cluster-scales surrounding the radio-loud brightest galaxy. We aim to investigate the…
By combining the REFLEX and NORAS cluster datasets with the NVSS radio catalogue, we obtain a sample of 145, z<0.3, X-ray selected clusters brighter than 3 10^(-12) erg/s/cm^2 that show a central radio emission above 3 mJy. For virial…
It has recently been proposed a theoretical model which accounts for the origin of radio mini-halos observed in some cooling flow clusters as related to electron re-acceleration by MHD turbulence (Gitti, Brunetti & Setti 2002). The MHD…
Hierarchical models of structure formation predict that galaxy clusters grow via mergers of smaller clusters and galaxy groups, as well as through continuous accretion of gas. MACS J0717.5+3745 is an X-ray luminous and complex merging…
Observations of diffuse, non-thermal radio emission spanning several megaparsecs have been documented in over 100 galaxy clusters. This emission, classified as giant radio halos (GHs), mini halos, and radio relics based mainly on their…
New radio data is presented for the rich cluster Abell 2163. The cluster radio emission is characterized by the presence of a radio halo, which is one of the most powerful and extended halos known so far. In the NE peripheral cluster…
Starburst galaxies are undergoing intense episodes of star formation. In these galaxies, gas is ejected into the surrounding environment through winds created by the effect of hot stars and supernova explosions. When interacting with the…
The presence of non-thermal electrons and large scale magnetic fields in the intra-cluster medium (ICM) is known through the detection of mega-parsec (Mpc) scale diffuse radio synchrotron emission. Although a significant amount of progress…
Centrally located diffuse radio emission has been observed in both merging and non-merging galaxy clusters. Depending on their morphology and size, we distinguish between giant radio haloes, which occur predominantly in merging clusters,…
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…
The radio spectral index map of the Coma halo shows a progressive steepening of the spectral index with increasing radius. Such a steepening cannot be simply justified by models involving continuous injection of fresh particles in the Coma…
Radio observations over the last two decades have provided evidence that diffuse synchrotron emission in the form of megaparsec-scale radio halos in galaxy clusters is likely tracing regions of the intracluster medium where relativistic…
A variety of large-scale diffuse radio structures have been identified in many clusters with the advent of new state-of-the-art facilities in radio astronomy. Among these diffuse radio structures, radio mini-halos are found in the central…
We report on the detection of a giant radio halo in the cluster Abell 3404 as well as confirmation of the radio halo observed in Abell 141 (with linear extents $\sim 770$ kpc and $\sim 850$ kpc, respectively). We use the Murchison Widefield…
New images of 7 radio halos and relics, obtained with the Very Large Array at 20 or 90 cm, are presented here. The existence of a cluster-wide radio halo in the clusters A 665 and CL 0016+16 is confirmed. Both these clusters share the…
Giant radio halos are Mpc-size sources found in some merging galaxy clusters. The synchrotron emitting electrons are thought to be (re)accelerated by plasma turbulence induced by the merging of two massive clusters. Cool core galaxy…
We report the discovery of a radio halo in the massive merging cluster MACSJ2243.3-0935, as well as a new radio relic candidate, using the Giant Meterwave Radio Telescope and the KAT-7 telescope. The radio halo is coincident with the…
We propose a simple estimator for the gravitational potential of cluster-size halos using the temperature and density profiles of the intracluster gas based on the assumptions of hydrostatic equilibrium and spherical symmetry. Using high…
Recent results on the radio emission from galaxy clusters are reviewed, with emphasis both on the radio galaxies and on the diffuse radio emission from the intracluster medium. We show that the formation of the tailed morphology in cluster…
We carry out a comprehensive Bayesian correlation analysis between hot halos and direct masses of supermassive black holes (SMBHs), by retrieving the X-ray plasma properties (temperature, luminosity, density, pressure, masses) over galactic…