The Effects of Turbulence on Three-Dimensional Magnetic Reconnection at the Magnetopause

TL;DR

This study uses particle-in-cell simulations to investigate how turbulence influences magnetic reconnection at the magnetopause, revealing turbulence's role in breaking the frozen-in condition and its coexistence with characteristic velocity space features.

Contribution

It demonstrates that turbulence significantly affects magnetic reconnection dynamics at the magnetopause and coexists with key observational features, expanding understanding beyond laminar models.

Findings

Turbulence develops in 3D reconnection, unlike in 2D.

Turbulence causes chaotic magnetic fields and enhances resistivity and viscosity.

Crescent-shaped velocity features persist despite turbulence.

Abstract

Two- and three-dimensional particle-in-cell simulations of a recent encounter of the Magnetospheric Multiscale Mission (MMS) with an electron diffusion region at the magnetopause are presented. While the two-dimensional simulation is laminar, turbulence develops at both the x-line and along the magnetic separatrices in the three-dimensional simulation. The turbulence is strong enough to make the magnetic field around the reconnection island chaotic and produces both anomalous resistivity and anomalous viscosity. Each contribute significantly to breaking the frozen-in condition in the electron diffusion region. A surprise is that the crescent-shaped features in velocity space seen both in MMS observations and in two-dimensional simulations survive, even in the turbulent environment of the three-dimensional system. This suggests that MMS's measurements of crescent distributions do not exclude the possibility that turbulence plays an important role in magnetopause reconnection.