Reconnection Properties of Large-Scale Current Sheets During Coronal Mass Ejection Eruptions

TL;DR

This study analyzes magnetic reconnection in large-scale current sheets during coronal mass ejections, revealing detailed properties, dynamics, and statistical behaviors consistent with high-resolution simulations.

Contribution

It provides a comprehensive analysis of reconnection properties in large-scale current sheets during CME eruptions, linking global evolution to local reconnection dynamics.

Findings

Reconnection rates reach up to 0.40 in inflow-to-outflow ratios.

Current sheets develop high aspect ratios up to 100:1.

Spectral index of magnetic energy fluctuations reflects current sheet evolution.

Abstract

We present a detailed analysis of the properties of magnetic reconnection at large-scale current sheets in a high cadence version of the Lynch & Edmondson (2013) 2.5D MHD simulation of sympathetic magnetic breakout eruptions from a pseudostreamer source region. We examine the resistive tearing and breakup of the three main current sheets into chains of X- and O-type null points and follow the dynamics of magnetic island growth, their merging, transit, and ejection with the reconnection exhaust. For each current sheet, we quantify the evolution of the length-to-width aspect ratio (up to $\sim$100:1), Lundquist number ($\sim$10$^3$), and reconnection rate (inflow-to-outflow ratios reaching $\sim$0.40). We examine the statistical and spectral properties of the fluctuations in the current sheets resulting from the plasmoid instability, including the distribution of magnetic island area, mass, and flux content. We show that the temporal evolution of the spectral index of the reconnection-generated magnetic energy density fluctuations appear to reflect global properties of the current sheet evolution. Our results are in excellent agreement with recent, high resolution reconnection-in-a-box simulations even though our current sheets' formation, growth, and dynamics are intrinsically coupled to the global evolution of sequential sympathetic CME eruptions.