Resolving Interchange Reconnection Dynamics in a Fan-Spine-like Topology Observed by Solar Orbiter

TL;DR

This study uses high-resolution Solar Orbiter observations to analyze the complex, quasi-periodic interchange reconnection dynamics in a small-scale fan-spine magnetic topology, revealing modulation by emerging structures and persistent outflows.

Contribution

It provides the first detailed analysis of interchange reconnection dynamics at high resolution in a small-scale fan-spine topology, highlighting their complexity and modulation mechanisms.

Findings

Reconnection exhibits a quasi-periodicity of ~200 seconds.

Multiple current sheets show continuous evolution and reversal.

A curtain-like feature generates persistent outflows near the null point.

Abstract

Interchange reconnection is believed to play a significant role in the production of solar jets and solar wind. However, the dynamics of interchange reconnection in the low corona might be more complex than recognized before in higher temporal and spatial resolutions. Using unprecedentedly high-resolution observations from the Extreme Ultraviolet Imager (EUI) onboard the Solar Orbiter, we analyze the dynamics of interchange reconnection in a small-scale fan-spine-like topology. Interchange reconnection that continuously occurs around the multi-null points of the fan-spine-like system exhibits a quasi-periodicity of ~200 s, nearly covering the entire evolution of this system. Continuous evolution and reversal of multiple current sheets are observed over time near the null point. These results reveal that the dynamics of interchange reconnection are likely modulated by the emerging magnetic structures, such as mini-filaments and emerging arcades. Moreover, a curtain-like feature with a width of 1.7 Mm is also observed near the interchange reconnection region and persistently generates outflows, which is similar to the separatrix curtain reported in the pseudo-streamer structure. This study not only demonstrates the complex and variable reconnection dynamics of interchange reconnection within small-scale fan-spine topology but also provides insights into the self-similarity of magnetic field configurations across multiple temporal and spatial scales.