# Observation of a reversal of breakout reconnection preceding a jet: evidence of oscillatory magnetic reconnection?

## TL;DR

This study observes a reversal in magnetic reconnection during a solar jet, providing evidence for oscillatory reconnection, a process previously theorized but not confirmed in the solar atmosphere.

## Contribution

It presents the first direct observational evidence of oscillatory magnetic reconnection in the solar atmosphere during a jet event.

## Key findings

- Detected a current sheet reversal before jet eruption.
- Observed the current sheet lengthening and shortening, indicating reconnection reversal.
- Provided evidence supporting the existence of oscillatory reconnection in solar plasma.

## Abstract

Recent studies have revealed that solar jets involving minifilament eruptions may be initiated under the well-known magnetic-breakout mechanism. Before or just at the onset of those jets, there should be a current sheet, where breakout magnetic reconnection takes place, between open fields and the outside of the jet-base arcade carrying minifilament in its core. In this paper we present a jet produced by eruption of two minifilaments lying at the jet base. A current sheet is directly detected near the jet base before the onset of the eruption, suggesting the magnetic-breakout mechanism. However, we further find that the current sheet undergoes a transition. The current sheet first shortens to zero in length, but then lengthens towards an orthogonal direction relative to its initial orientation. The change of the current sheet gives rise to a reversal of the breakout reconnection, as the inflow and outflow regions before the transition become the outflow and inflow regions after the transition, respectively. We therefore propose that this observation provides evidence for the so-called oscillatory reconnection which is defined by a series of reconnection reversals but not yet proved to exist in real plasma environment of the solar atmosphere.