Radio Halos, cluster mergers and the role of future LOFAR observations
arXiv:1103.5031
Abstract
A radio bimodality is observed in galaxy clusters: a fraction of clusters host giant radio halos while the majority of clusters do not show evidence of diffuse cluster-scale radio emission. Present data clearly suggest that the radio bi-modality has a correspondence in terms of dynamical state of the hosting clusters. I will report on these evidences in some details and discuss the role of cluster mergers in the generation of giant radio halos and their evolution. Finally I will report on expectations on the statistical properties of radio halos assuming that the emitting electrons are re-accelerated by merger-turbulence, and discuss the role of incoming LOFAR surveys.
6 pages, 3 figures, invited talk at the conference "Non-thermal phenomena in colliding galaxy clusters", held in Nice (F), 15-18 November 2010, to be published on Mem. SAIt