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arXiv · 2103.01388

The Biermann battery driven by a streaming plasma

Yutaka Ohira
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Abstract

The Biermann battery is a promising generation mechanism of a seed magnetic field in the universe. We propose a new driving mechanism for the Biermann battery in an inhomogeneous plasma with a beam component. An inhomogeneous electron flow induced by the return current can make an electron pressure gradient which is not parallel to the density gradient. As a result, the magnetic field is generated by the Biermann battery. We demonstrate the new generation mechanism of the magnetic field by conducting three-fluid plasma simulations. By this mechanism, the first cosmic rays can generate the seed magnetic field with astrophysical scales at redshift around 20.

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Yutaka Ohira. 2021-03-02. The Biermann battery driven by a streaming plasma. https://doi.org/10.3847/1538-4357%2Fabec41

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