Fast magnetic reconnection in the plasmoid-dominated regime

TL;DR

This paper proposes a stochastic plasmoid chain model for resistive magnetic reconnection, showing the reconnection rate is independent of Lundquist number and revealing flux distribution and large plasmoid emergence.

Contribution

It introduces a new conceptual model for magnetic reconnection that accounts for plasmoid dynamics and provides criteria for regime transitions.

Findings

Reconnection rate is independent of Lundquist number.

Flux distribution follows an inverse square law.

Large plasmoids can disrupt the chain and cause observable events.

Abstract

A conceptual model of resistive magnetic reconnection via a stochastic plasmoid chain is proposed. The global reconnection rate is shown to be independent of the Lundquist number. The distribution of fluxes in the plasmoids is shown to be an inverse square law. It is argued that there is a finite probability of emergence of abnormally large plasmoids, which can disrupt the chain (and may be responsible for observable large abrupt events in solar flares and sawtooth crashes). A criterion for the transition from magnetohydrodynamic to collisionless regime is provided.