2001NewA....6....1B

We calculate the energy distribution of the relativistic particles injected in the ICM during a phase of reacceleration of the relativistic particles in the cluster volume. We apply our results to the case of the Coma clusterin which recent merging activity and the presence of a radio halo may suggest that reacceleration processes are efficient. We find that the electron population injected in the central part of the cluster by the head tail radio galaxy NGC 4869 may account for a large fraction, if not all, of the detected EUV excess via inverse Compton scattering of the cosmic microwave background (CMB) photons. If radio haloes are powered by reacceleration mechanisms active in the cluster volume, moderate non-thermal EUV excesses (of the order ∼1-5.1042 erg s-1) should be a common feature of clusters containing powerful head tail radio galaxies and/or AGNs.