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arXiv · 2107.12945

Production of a chiral magnetic anomaly with emerging turbulence and mean-field dynamo action

Jennifer Schober·Igor Rogachevskii·Axel Brandenburg
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Abstract

In relativistic magnetized plasmas, asymmetry in the number densities of left- and right-handed fermions, i.e., a non-zero chiral chemical potential mu_5, leads to an electric current along the magnetic field. This causes a chiral dynamo instability for a uniform mu_5, but our simulations reveal a dynamo even for fluctuating mu_5 with zero mean. It produces magnetically-dominated turbulence and generates mean magnetic fields via the magnetic alpha effect. Eventually, a universal scale-invariant k^(-1) spectrum of mu_5 and a k^(-3) magnetic spectrum are formed independently of the initial condition.

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Jennifer Schober, Igor Rogachevskii, Axel Brandenburg. 2022-02-12. Production of a chiral magnetic anomaly with emerging turbulence and mean-field dynamo action. https://doi.org/10.1103/physrevlett.128.065002

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