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The aim of this work is to analyse the radio properties of the massive and dynamical disturbed clusters Abell 1451 and Zwcl 0634.1+4750, especially focusing on the possible presence of diffuse emission. We present new GMRT 320 MHz and JVLA 1.5 GHz observations of these two clusters. We found that both Abell 1451 and Zwcl 0634.1+4750 host a radio halo with a typical spectrum ($alphasim1-1.3$). Similarly to a few other cases reported in the recent literature, these radio halos are significantly fainter in radio luminosity with respect to the current radio power-mass correlations and they are smaller than classical giant radio halos. These underluminous sources might contribute to shed light on the complex mechanisms of formation and evolution of radio halos. Furthermore, we detected a candidate radio relic at large distance from the cluster center in Abell 1451 and a peculiar head tail radio galaxy in Zwcl 0634.1+4750, which might be interacting with a shock front.
Early science observations from the Australian Square Kilometre Array Pathfinder (ASKAP) have revealed clear signals of diffuse radio emission associated with two clusters detected by the South Pole Telescope via their Sunyaev Zeldovich signal. SPT C
We review models for giant radio halos in clusters of galaxies, with a focus on numerical and theoretical work. After summarising the most important observations of these objects, we present an introduction to the theoretical aspects of hadronic mode
Collisions between galaxy clusters dissipate enormous amounts of energy in the intra-cluster medium (ICM) through turbulence and shocks. In the process, Mpc-scale diffuse synchrotron emission in form of radio halos and relics can form. However, littl
We present the first high resolution MHD simulation of cosmic-ray electron reacceleration by turbulence in cluster mergers. We use an idealised model for cluster mergers, combined with a numerical model for the injection, cooling and reacceleration o
A possibility of generating a population of cosmic-ray particles accelerated in supernovae typeIa (SNIa) remnants in the intracluster medium (ICM) is discussed. The presently constrained host-less SNIa rates in the clusters are found to be sufficient