Seminar: Polarised radio emission and magnetic fields in galaxy clusters and large-scale structure

Prof Kinwah Wu

Mullard Space Science Laboratory, University College London

Some galaxy clusters, e.g. halo and relic sources, are found to be strong radio sources. It is evident that the hot gases in galaxy clusters are  permeated by magnetic fields. The pressing questions are now: what is the origin of the magnetic fields  in galaxy clusters and superclusters? And what are the morphological structures of the magnetic fields in the intracluster and intercluster media?

I will address these issues and discuss how the polarization of radio emission can be used to infer structural properties of magnetic fields in galaxy clusters and larger-scale structures.  I will present my recent numerical polarized radiative transfer calculations of radio synchrotron radiation from galaxy clusters and large-scale superclusters (obtained by semi-analytic models as well as by numerical hydrodynamics simulations) and the corresponding synthetic intensity and polarization images of galaxy clusters and large-scale structure.

I will also show how the  spatial correlation of radio polarization depends on the structures of the magnetic fields in the intracluster and intercluster media. The calculations will be useful for  future SKA observational studies of large astrophysical structures.