The interplay between cosmic rays and magnetic turbulence in galaxy   clusters: radio halos and gamma rays
  The interaction of magnetic turbulence and relativistic particles is a important process for understanding particles propagation and acceleration in many astrophysical environments. Large-scale turbulence can be generated in the intra-cluster-medium (ICM) during mergers between galaxy clusters and affects their non-thermal properties. Giant radio halos, Mpc-scale synchrotron sources observed in merging clusters, may probe the connection between turbulence and non-thermal cluster-scale emission. After discussing relevant aspects of the physics of turbulence and turbulent acceleration in the ICM, I will focus on recent advances in the modeling of non-thermal emission from galaxy clusters. 
Gianfranco Brunetti
astro-ph.CO astro-ph.HE