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Properties of Simulated Magnetized Galaxy Clusters

Klaus Dolag
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Abstract

We study the evolution of magnetized clusters in a cosmological environment using magneto-hydro dynamical simulations. Large scale flows and merging of subclumps generate shear flows leading to Kelvin-Helmholtz instabilities, which, in addition to the compression of the gas where the magnetic field is frozen in, further amplify the magnetic field during the evolution of the cluster. Therefore, well-motivated initial magnetic fields of $ ^{1/2}=10^{-9} {\rm G}$ reach the observed $\simμ{\rm G}$ field strengths in the cluster cores at $z=0$. These magnetized clusters can be used to study the final magnetic field structure, the dynamical importance of magnetic fields for the interpretation of observed X-Ray properties, and help to constrain further processes in galaxy clusters like the population of relativistic particles giving rise to the observed radio halos or the behavior of magnetized cooling flows.

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Klaus Dolag. 2000-10-07. Properties of Simulated Magnetized Galaxy Clusters. https://arxiv.org/abs/astro-ph/0010149

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