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arXiv · 2606.25580

The magnetic field in the Milky Way Galaxy: from large to small scales

Xiaohui Sun·Jennifer West·Marijke Haverkorn·Andrea Bracco·Anna Ordog·Sui Ann Mao·Yik Ki Ma·Wenhui Jing·Thiem Hoang
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Abstract

The Milky Way is the galaxy in which we can study its magnetic field to the finest details, providing an ideal laboratory to understand the fundamental questions: how magnetic field is generated and evolves, and how it influences other components in the Galaxy. An SKA-Mid polarization survey will produce an all-sky rotation measure (RM) grid with a density of about 100 per square degree, which is approximately two orders of magnitude larger than what is currently available, and produce total intensity, polarized intensity, and RM all-sky images of diffuse emission covering scales from about 10 arcseconds upward after combination with single-dish observations. The dense RM grid and images of diffuse emission will allow us to determine the most complete picture of the magnetic field in the southern Galactic hemisphere from large to small scales.

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Xiaohui Sun, Jennifer West, Marijke Haverkorn, Andrea Bracco, Anna Ordog, Sui Ann Mao, Yik Ki Ma, Wenhui Jing, Thiem Hoang. 2026-06-24. The magnetic field in the Milky Way Galaxy: from large to small scales. https://arxiv.org/abs/2606.25580

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