Transition to super-diffusive transport in turbulent plasmas

TL;DR

This paper studies how charged particles in turbulent plasmas transition from diffusive to ballistic transport as their Larmor radius increases, highlighting the role of twistless invariant tori in this process.

Contribution

It reveals the mechanism behind the transition to super-diffusive transport in turbulent plasmas through nonlinear dynamics analysis.

Findings

Transition from diffusive to ballistic transport with increasing Larmor radius

Twistless invariant tori are key to the transport transition

Transport properties are drastically affected by these invariant structures

Abstract

We investigate the motion of charged particles in a turbulent electrostatic potential using guiding-center theory. By increasing the Larmor radius, the dynamics exhibit close-to-ballistic transport properties. The transition from diffusive to ballistic transport is analyzed using nonlinear dynamics. It is found that twistless invariant tori in the guiding-center dynamics are responsible for this transition, drastically affecting transport properties of charged particles.