Resolving 4-D Nature of Magnetism with Depolarization and Faraday Tomography: Japanese SKA Cosmic Magnetism Science

TL;DR

This paper discusses how the upcoming Square Kilometre Array (SKA) will revolutionize our understanding of cosmic magnetic fields through advanced polarimetry techniques like depolarization and Faraday Tomography, enabling 4-D mapping of magnetism.

Contribution

The paper introduces the SKA-JP project focused on using depolarization and Faraday Tomography to explore the 4-D nature of cosmic magnetism across various astronomical objects.

Findings

SKA will provide unprecedented sensitivity for magnetic field studies.

Wideband polarimetry enables detailed sightline magnetic field analysis.

The project includes ten scientific use cases for cosmic magnetism.

Abstract

Magnetic fields play essential roles in various astronomical objects. Radio astronomy has revealed that magnetic fields are ubiquitous in our Universe. However, the real origin and evolution of magnetic fields is poorly proven. In order to advance our knowledge of cosmic magnetism in coming decades, the Square Kilometre Array (SKA) should have supreme sensitivity than ever before, which provides numerous observation points in the cosmic space. Furthermore, the SKA should be designed to facilitate wideband polarimetry so as to allow us to examine sightline structures of magnetic fields by means of depolarization and Faraday Tomography. The SKA will be able to drive cosmic magnetism of the interstellar medium, the Milky Way, galaxies, AGN, galaxy clusters, and potentially the cosmic web which may preserve information of the primeval Universe. The Japan SKA Consortium (SKA-JP) Magnetism Science Working Group (SWG) proposes the project "Resolving 4-D Nature of Magnetism with Depolarization and Faraday Tomography", which contains ten scientific use cases.