Quiet Sun Explosive Events: Jets, Splashes, and Eruptions

TL;DR

This paper investigates small-scale explosive events in the quiet Sun, revealing jet-like flows triggered by magnetic reconnection at supergranular junctions through multi-wavelength observations.

Contribution

It provides the first detailed analysis linking quiet Sun explosive events to magnetic reconnection and jet-like flows using SDO and SUMER data.

Findings

Explosive events are associated with jet-like flows and magnetic reconnection.

Events occur near supergranular network junctions and flux cancellation sites.

Three distinct event types are characterized with plasma ejections, flux cancellation, and mini-CME bases.

Abstract

Explosive events are small transition region phenomena characterised by broad non-Gaussian wings in their line profiles. Images from the Solar Dynamics Observatory (SDO) give a first view of the plasma dynamics at the sites of explosive events seen in O VI spectra of a region of quiet Sun, taken with the ultraviolet spectrometer SUMER/SOHO. Distinct event bursts were seen either at the junction of supergranular network cells or near emerging flux. Three are described in the context of their surrounding transition region (304 A) and coronal (171 A) activity. One showed plasma ejected from one footpoint of a small loop which resulted in a `splash' at the other footpoint. The second was related to flux cancellation, inferred from SDO/HMI magnetograms, and a coronal dimming surrounded by a ring of bright EUV emission with explosive events at positions where the spectrometer slit crossed the bright ring. The third series of events occurred at the base of a slow mini-CME. All events studied here imply jet-like flows probably triggered by magnetic reconnection at supergranular junctions. Events come from sites close to the footpoints of jets seen in AIA images, and possibly from the landing site of induced high velocity flows. They are not caused by rapid rotation in spicules.