The Impact of Dense RM Grids on the Study of Intra-cluster and Intra-group Magnetic Fields

The presence of diffuse radio sources in galaxy clusters and the recent discovery of polarized signals associated with the tails of a jellyfish galaxy indicates that intra-cluster/intra-group magnetic fields can influence the physics of these environments and the evolution of the embedded galaxies. A better reconstruction of the properties of such fields is therefore fundamental to understand in detail the physical processes in galaxy groups and clusters and the evolution of the embedded sources. The SKAO represents a great opportunity to perform these studies through the analysis of the so-called rotation measure (RM) grid, since polarization properties of radio sources are modified by the intervening magnetic field. In this manuscript, we illustrate the prediction on the density of the RM grid considering the SKA-mid polarization survey planned by the SKA Magnetism Science Working Group. Moreover, we describe how it is possible to measure intra-cluster/intra-group magnetic fields with the RM grid. Eventually, we quantify the improvement in the precision and accuracy of the magnetic field measurements compared to what is achievable with current surveys such as the POSSUM survey.