Understanding the intra-cluster medium through radio surveys of galaxy clusters
National Centre for Radio Astrophysics (NCRA), Pune India
The life-cycle of cosmic rays and magnetic fields in galaxy clusters is at the root of understanding the formation and evolution of radio sources in the intra-cluster medium (ICM). Radio galaxies, radio halos, radio relics and mini-halos are the different types of radio sources in galaxy clusters. The origin and evolution of these sources and their inter-dependence is still not understood. Deep radio observations in the past decade have revealed some of the properties and are helping to constrain the theoretical models. The Extended GMRT Radio Halo survey (EGRHS) is a systematic deep radio survey of galaxy clusters that provided the statistics of occurrence of such sources in a sample of 65 most X-ray luminous galaxy clusters in the redshift range 0.2 - 0.4. I will describe the results from this survey and from our follow-up of other interesting sources in galaxy clusters. The next generation telescopes such as the LOFAR, upgraded GMRT and the Jansky VLA are already showing the discovery space that is still open in galaxy clusters. In the context of these results, I will briefly describe the promise held by the future radio surveys with the Square Kilometer Array and its precursors including the upgraded GMRT.
Date: Lundi, le 28 août 2017 Heure: 12:30 Lieu: Université de Montréal Pavillon Roger-Gaudry, Local D-460