Non-Thermal Electron Energization from Magnetic Reconnection in Laser-Driven Plasmas

TL;DR

This paper demonstrates through simulations that laser-driven plasma experiments can produce non-thermal electrons with energies significantly higher than thermal energies via magnetic reconnection, offering a new experimental platform.

Contribution

It shows that current laboratory plasma conditions can generate non-thermal electrons through reconnection, with detailed acceleration mechanisms and energy spectra analysis.

Findings

Non-thermal electrons can reach energies over ten times the initial thermal energy.

Electrons are accelerated by reconnection electric fields and trapped in plasmoids.

Up to 8% of initial electron energy and 24% of magnetic energy are converted into non-thermal electrons.

Abstract

The possibility of studying non-thermal electron energization in laser-driven plasma experiments of magnetic reconnection is studied using two- and three-dimensional particle-in-cell simulations. It is demonstrated that non-thermal electrons with energies more than an order of magnitude larger than the initial thermal energy can be produced in plasma conditions currently accessible in the laboratory. Electrons are accelerated by the reconnection electric field, being injected at varied distances from the X-points, and in some cases trapped in plasmoids, before escaping the finite-sized system. Trapped electrons can be further energized by the electric field arising from the motion of the plasmoid. This acceleration gives rise to a non-thermal electron component that resembles a power-law spectrum, containing up to ~ 8% of the initial energy of the interacting electrons and ~ 24 % of the initial magnetic energy. Estimates of the maximum electron energy and of the plasma conditions required to observe suprathermal electron acceleration are provided, paving the way for a new platform for the experimental study of particle acceleration induced by reconnection.