First-Principles Fermi Acceleration in Magnetized Turbulence
Martin Lemoine
Abstract
This Letter provides a concrete implementation of 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.
Topics & Concepts
PhysicsTurbulenceAccelerationFermi Gamma-ray Space TelescopeFermi accelerationQuantum electrodynamicsStatistical physicsParticle accelerationClassical mechanicsCondensed matter physicsMechanicsSolar and Space Plasma DynamicsQuantum, superfluid, helium dynamicsCosmology and Gravitation Theories