Reconnection in weakly stochastic B-fields in 2D

TL;DR

This study investigates magnetic reconnection in 2D turbulent plasmas, revealing that turbulence influences reconnection topology but does not lead to fast reconnection, with reconnection speed depending on resistivity.

Contribution

It demonstrates that in 2D turbulence, reconnection speed remains resistivity-dependent and does not become fast, contrasting with 3D cases.

Findings

Turbulence alters magnetic field topology near the current sheet.

Reconnection speed depends on resistivity and does not become fast.

Turbulence causes large fluctuations in reconnection speed.

Abstract

We study two dimensional turbulent magnetic reconnection in a compressible fluid in the gas pressure dominated limit. We use open boundary conditions and start from a Harris current sheet configuration with a uniform total pressure. A small perturbation to the vector potential initiates laminar reconnection at the Sweet-Parker rate, which is allowed to evolve for several dynamical times. Subsequently sub-Alfvenic turbulence is produced through random forcing at small wave numbers. The magnetic field topology near the current sheet is strongly affected by the turbulence. However, we find that the resulting reconnection speed depends on the resistivity. In contrast to previous results in three dimensions, we find no evidence for fast reconnection. The reconnection speed exhibits large variations but the time averages increase smoothly with the strength of the turbulence.