Simulation Study of Solar Plasma Eruptions Caused by Interactions between Emerging Flux and Coronal Arcade Fields

TL;DR

This study uses 2D MHD simulations to explore how interactions between emerging flux and coronal arcade fields trigger solar plasma eruptions, identifying two main mechanisms depending on flux location.

Contribution

It reveals two distinct eruption mechanisms based on flux position and provides a simple formula for eruption conditions, advancing understanding of solar plasma eruptions.

Findings

Two eruption mechanisms depend on flux location.

Reconnection is essential in one mechanism, not in the other.

A simple formula predicts eruptive conditions.

Abstract

We investigate the triggering mechanisms of plasma eruptions in the solar atmosphere due to interactions between emerging flux and coronal arcade fields by using two-dimensional MHD simulations. We perform parameter surveys with respect to arcade field height, magnetic field strength, and emerging flux location. Our results show that two possible mechanisms exist, and which mechanism is dominant depends mostly on emerging flux location. One mechanism appears when the location of emerging flux is close to the polarity inversion line (PIL) of an arcade field. This mechanism requires reconnection between the emerging flux and the arcade field, as pointed out by previous studies. The other mechanism appears when the location of emerging flux is around the edge of an arcade field. This mechanism does not require reconnection between the emerging flux and the arcade field but does demand reconnection in the arcade field above the PIL. Furthermore, we found that the eruptive condition for this mechanism can be represented by a simple formula.