Study of Polarized Emission in Radio Halos and Filaments in the SKA Telescopes Era

Valentina Vacca; Federica Govoni; Matteo Murgia; Paolo Marchegiani; Hui Li; Myriam Gitti; Francesca Loi; Luigina Feretti; Ettore Carretti; Elia Battistelli; Andrea Cabriolu; Torsten A. Ensslin; Chiara Ferrari; Gabriele Giovannini; Richard A. Perley

arXiv · 2606.25616

Study of Polarized Emission in Radio Halos and Filaments in the SKA Telescopes Era

Valentina Vacca·Federica Govoni·Matteo Murgia·Paolo Marchegiani·Hui Li·Myriam Gitti·Francesca Loi·Luigina Feretti·Ettore Carretti·Elia Battistelli·Andrea Cabriolu·Torsten A. Ensslin·Chiara Ferrari·Gabriele Giovannini·Richard A. Perley

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Abstract

Synchrotron diffuse emission in merging galaxy clusters and along filaments connecting them demonstrates the presence of relativistic particles and magnetic fields in these environments. The study of the polarized signal associated with this emission represents a powerful tool to constrain the properties of intracluster magnetic fields and the physics of acceleration and transport of relativistic particles. Despite technological progress, detecting this polarized signal is still very challenging. In order to shed light on the capabilities of the SKA telescopes to study this emission, we use the data of cosmological magneto-hydro-dynamic simulations to predict the expected polarized surface brightness of diffuse synchrotron sources from the center of galaxy clusters to filaments of the cosmic web at 1.4 GHz. We explore the possibility to detect these sources with a polarization survey with SKA-Mid with AA4 telescopes and compare the results with those from pointed observations corresponding to longer exposure times. These simulations provide precious information to understand the potential of the SKA telescopes for studying the origin and evolution of cosmological magnetic fields. We discuss how these observations can be used in order to characterize the magnetic field and the distribution and energy content of the radio emitting plasma and to shed light on the link between non-thermal and thermal properties and the dynamical state of the system.

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Valentina Vacca, Federica Govoni, Matteo Murgia, Paolo Marchegiani, Hui Li, Myriam Gitti, Francesca Loi, Luigina Feretti, Ettore Carretti, Elia Battistelli, Andrea Cabriolu, Torsten A. Ensslin, Chiara Ferrari, Gabriele Giovannini, Richard A. Perley. 2026-06-24. Study of Polarized Emission in Radio Halos and Filaments in the SKA Telescopes Era. https://arxiv.org/abs/2606.25616

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