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arXiv · 1211.4356

Magnetic fields during high redshift structure formation

Dominik R. G. Schleicher·Muhammad Latif·Jennifer Schober·Wolfram Schmidt·Stefano Bovino·Christoph Federrath·Jens Niemeyer·Robi Banerjee·Ralf S. Klessen
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Abstract

We explore the amplification of magnetic fields in the high-redshift Universe. For this purpose, we perform high-resolution cosmological simulations following the formation of primordial halos with \sim10^7 M_solar, revealing the presence of turbulent structures and complex morphologies at resolutions of at least 32 cells per Jeans length. Employing a turbulence subgrid-scale model, we quantify the amount of unresolved turbulence and show that the resulting turbulent viscosity has a significant impact on the gas morphology, suppressing the formation of low-mass clumps. We further demonstrate that such turbulence implies the efficient amplification of magnetic fields via the small-scale dynamo. We discuss the properties of the dynamo in the kinematic and non-linear regime, and explore the resulting magnetic field amplification during primordial star formation. We show that field strengths of \sim10^{-5} G can be expected at number densities of \sim5 cm^{-3}.

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Dominik R. G. Schleicher, Muhammad Latif, Jennifer Schober, Wolfram Schmidt, Stefano Bovino, Christoph Federrath, Jens Niemeyer, Robi Banerjee, Ralf S. Klessen. 2012-11-19. Magnetic fields during high redshift structure formation. https://doi.org/10.1002/asna.201211898

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