Quiet Sun H\alpha\ Transients and Corresponding Small-Scale Transition Region and Coronal Heating

TL;DR

This study statistically links small-scale H-alpha transients, specifically RBEs and RREs, to a significant portion of quiet Sun transition region and coronal brightenings, highlighting their role in solar atmospheric heating.

Contribution

It provides the first statistical evidence quantifying the contribution of RBEs and RREs to quiet Sun coronal and transition region heating using high-resolution, full-disk observations.

Findings

At least 11% of low-coronal brightenings are linked to RBEs or RREs.

Approximately 6% of detected events in 171 diagnostics match H-alpha features.

Strong visual correlations between coronal events and co-evolving RBEs/RREs.

Abstract

Rapid Blue- and Red-shifted Excursions (RBEs and RREs) are likely to be the on-disk counterparts of Type II spicules. Recently, heating signatures from RBEs/RREs have been detected in IRIS slit-jaw images dominated by transition-region lines around network patches. Additionally, signatures of Type II spicules have been observed in AIA diagnostics. The full-disk, ever-present nature of the AIA diagnostics should provide us with sufficient statistics to directly determine how important RBEs and RREs are to the heating of the transition region and corona. We find, with high statistical significance, that at least 11% of the low-coronal brightenings detected in a quiet-Sun region in 304, can be attributed to either RBEs or RREs as observed in H\alpha, and a 6% match of 171 detected events to RBEs or RREs with very similar statistics for both types of H\alpha\ features. We took a statistical approach that allows for noisy detections in the coronal channels and provides us with a lower, but statistical significant, bound. Further, we consider matches based on overlapping features in both time and space, and find strong visual indications of further correspondence between coronal events and co-evolving but non-overlapping, RBEs and RREs.