On Calculating Diffusion Coefficients Numerically in Synthetic Turbulence Using Particle Pushers

Abstract

Numerical simulations of test particle transport in the presence of synthetic turbulence with known properties still provide the most reliable estimations of the diffusion coefficients of charged particles in turbulent space plasmas available. The development and implementation of such simulations, however, are far from straightforward. The present study provides a comprehensive treatment of the development and testing of such a simulation code, detailing the simulation of synthetic turbulence and diffusion coefficients, as well as various numerical tests to validate code output. Furthermore, a novel test for such codes is proposed, namely, the transport of charged particles in pure slab turbulence, which proves sensitive to numerical factors prior tests remain insensitive to.