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arXiv · 2210.01038

First-principles Fermi acceleration in magnetized turbulence

Martin Lemoine
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Abstract

This work provides a concrete implementation of E. Fermi's model of particle acceleration in magnetohydrodynamic (MHD) turbulence, connecting the rate of energization to the gradients of the velocity of magnetic field lines, which it characterizes within a multifractal picture of turbulence intermittency. It then derives a transport equation in momentum space for the distribution function. This description is shown to be substantiated by a large-scale numerical simulation of strong MHD turbulence. The present, general framework can be used to model particle acceleration in a variety of environments.

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Martin Lemoine. 2022-10-03. First-principles Fermi acceleration in magnetized turbulence. https://doi.org/10.1103/physrevlett.129.215101

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