Astronomy and Astrophysics Seminars
Low Frequency view of merging galaxy clusters
by Dr. M. PANDEY-POMMIER (Observatoire de Lyon, France)
Friday, November 20, 2015
from
to
(Asia/Kolkata)
at DAA ( A269 )
at DAA ( A269 )
Description |
Cluster of galaxies are the largest gravitationally bounded systems in our Universe. They emit non-thermal emission during merger events that takes the form of cluster wide (Mpc-size) radio halos, mini-halos and relics, further implying the presence of relativistic particles and magnetic fields within the intracluster medium. These sources reveal a population of ultra-relativistic electrons coexisting with the intracluster thermal gas. The origin of these relativistic electrons is one of the most intriguing problems of cluster astrophysics. Further, the radio observations also show presence of micro-Gauss level magnetic fields within the galaxy clusters, with values up to tens of μG at the center of cooling core clusters. In this presentation, I will discuss about the new results on the low frequency nature of a few galaxy clusters observed with the GMRT and LOFAR as well as their statistical properties. I will also outline the important contribution that are expected in this area from sophisticated radio facilities (like LOFAR, SKA, etc.) as well as synergies with ongoing survey with Multi Unit Spectroscopic Explorer (MUSE) and India's first dedicated multi-wavelength space observatory, ASTROSAT. |