FUNA Lunch Talk:

Gianfranco Brunetti

Istituto di RadioAstronomia CNR, Bologna

Non thermal components and particle acceleration in clusters of galaxies

May 23

12:10PM, Room 230, NRAO, Edgemont Road


Radio observations of diffuse synchrotron emission from galaxy clusters are the most important evidences for non thermal components (relativistic particles and magnetic fields) in the intergalactic medium. Understanding the origin and evolution of these components is crucial because they are sources of pressure, they control particle transport in the intergalactic medium and they are likely related to the dark matter- driven cluster-cluster mergers. In the first part of the talk I will review the observational and theoretical "status of the art" on this topic. Several observational facts suggest that turbulence driven by cluster mergers in the intergalactic medium may play an important role in the acceleration process of relativistic electrons (and protons). Thus in the second part of the talk I will focus on this physics and on the most important expectations of this scenario in different observational bands. Finally I will discuss the importance of future observations, at low radio frequencies (with LOFAR, LWA) and in the gamma rays (GLAST), in addressing the physics of non thermal components in galaxy clusters, and also the importance of X-ray observations with future hard X-ray telescopes.