Merging galaxies and clusters: Insights into the role of magnetic fields and the physics of radio relics
arXiv:2607.14426 · doi:10.25932/publishup-67622
The thesis uses high‑resolution cosmological magnetohydrodynamic simulations to study how magnetic fields evolve during galaxy mergers and how shock‑driven radio relics form in merging galaxy clusters.
Abstract
Mergers have long been understood to be a driver of galaxy and galaxy cluster evolution. They release tremendous amounts of gravitational potential energy - ~ and ~ ergs in galaxies and clusters, respectively - which is dissipated in powerful shock waves. In galaxies especially, the strong tidal effects can have profound effects on the remnant morphology. Although the modelling of mergers has a long history, it is only recently that it has been fully appreciated just how sensitive they are to a range of factors, including the existence of circumgalactic media (CGM), accretion along filaments, and pre-existing magnetic fields. Modelling these aspects in a cosmologically-consistent manner necessitates the use of high-resolution cosmological magnetohydrodynamic (MHD) simulations. In this work, we use such simulations to investigate two distinct merger-related phenomena: i) magnetic fields in galaxy mergers, and ii) the origin of radio relics in galaxy clusters.
PhD Thesis, University of Potsdam (2025), xii + 228 pages. Ch. 3-5 reprint arXiv:2011.13947, arXiv:2301.13208, and arXiv:2411.11947, resp. Ch. 6 is expanded in arXiv:2604.06302. Ch. 7 describes major revisions to the CREST and AREPO shock finder implementations; cite this work for these developments