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OATS-DAUT SEMINAR
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Speaker: Luigina Feretti (INAF/Istituto di Radioastronomia, BO)

Title: Radio emission in clusters of galaxies

Date: Wednesday, September 20th, 2006
Time: 12:00 noon
Venue: Villa Bazzoni

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Abstract: An important component of the intracluster medium in galaxy clusters is represented by a population of relativistic particles, which interact with large-scale magnetic fields producing diffuse synchrotron emission detected at radio wavelengths. Diffuse radio sources of the order of Mpc in size have been detected in clusters both in central regions (halos) and in peripheral regions (relics). Observational results provide evidence that these phenomena are connected to the structure formation process: indeed a cluster merger activity is likely to supply the energy for the maintenance of halos and relics. I will present recent results on the spectral index distibution of radio halos, showing a strict connection to the cluster merger, and I will briefly outline the mechanisms responsible for the energy transfer from cluster mergers to the radio emitting particles.
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