Interchange instability and transport in matter-antimatter plasmas

TL;DR

This paper investigates the interchange instability and transport phenomena in matter-antimatter plasmas, deriving scaling relations for density blob propagation, verified by simulations, with implications for magnetic confinement in experiments.

Contribution

It introduces new scaling relations for blob propagation in electron-positron plasmas, including damping effects, and generalizes the model to other matter-antimatter systems.

Findings

Scaling relations for blob velocity derived and verified.

Results support feasible magnetic confinement for planned experiments.

Matter-antimatter separation may hinder sustained confinement.

Abstract

Symmetric electron-positron plasmas in inhomogeneous magnetic fields are intrinsically subject to interchange instability and transport. Scaling relations for the propagation velocity of density blob perturbations relevant to transport in isothermal magnetically confined electron-positron plasmas are deduced, including damping effects when Debye lengths are large compared to Larmor radii. The relations are verified by nonlinear full-F gyrofluid computations. Results are in favour of sufficient magnetic confinement for planned electron-positron plasma experiments. The model is generalised to other matter-antimatter plasmas. Magnetised electron-positron-proton-antiproton plasmas are susceptible to interchange driven local matter-antimatter separation, which can be expected to impede (so far unrealised) sustained laboratory magnetic confinement.