2008/07/23 by Motokazu Takizawa · 31 citations
Physics and Astronomy · #Astrophysics #Astrophysics and Star Formation Studies #Cluster (spacecraft) #Computational physics #Faraday effect #Field (mathematics) #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy cluster #Geometry #Magnetic field #Physics #Rotation (mathematics) #Solar and Space Plasma Dynamics #Substructure #astro-ph
paper · pdf · doi:10.1086/592059
published in The Astrophysical Journal 687(2), 951-958 (IOP Publishing) · Accepted for publication in ApJ
arxiv created 2008/07/23 · openalex publication_date 2008/10/31 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
We present results from N -body + magnetohydrodynamical simulations of merging clusters of galaxies. We find that cluster mergers cause various characteristic magnetic field structures because of the strong bulk flows in the intracluster medium. The moving substructures result in cool regions surrounded by the magnetic field. These will be recognized as magnetized cold fronts in the observational point of view. A relatively ordered magnetic field structure is generated just behind the moving substructure. Eddylike field configurations are also formed by Kelvin-Helmholtz instabilities. These features are similarly seen even in off-center mergers, although the detailed structures change slightly. The above-mentioned characteristic magnetic field structures are partly recognized in Faraday rotation measure maps. The higher absolute values of the rotation measure are expected when observed along the collision axis, because of the elongated density distribution and relatively ordered field structure along the axis. The rotation measure maps on the cosmic microwave background radiation, which covers clusters entirely, could be useful probes of not only the magnetic field structures but also the internal dynamics of the intracluster medium.