Fast magnetic reconnection in three dimensional MHD simulations

TL;DR

This paper demonstrates a numerical example of fast magnetic reconnection in 3D MHD simulations, revealing that global flows drive the process with regions interacting dynamically, releasing half of the magnetic energy rapidly.

Contribution

It provides a constructive 3D simulation showing fast magnetic reconnection driven by global flows, with a detailed physical picture of the process.

Findings

Approximately 50% of magnetic energy is released in about one Alfven time.

Reconnection regions are dynamic and interact with each other.

Reconnection occurs via X-like points similar to Petschek reconnection.

Abstract

We present a constructive numerical example of fast magnetic reconnection in a three dimensional periodic box. Reconnection is initiated by a strong, localized perturbation to the field lines. The solution is intrinsically three dimensional, and its gross properties do not depend on the details of the simulations. $\sim 50%$ of the magnetic energy is released in an event which lasts about one Alfven time, but only after a delay during which the field lines evolve into a critical configuration. We present a physical picture of the process. The reconnection regions are dynamical and mutually interacting. In the comoving frame of these regions, reconnection occurs through an X-like point, analogous to Petschek reconnection. The dynamics appear to be driven by global flows, not local processes.