The effects of transients on photospheric and chromospheric power distributions

TL;DR

This study investigates how small-scale solar transients like mottles, RBEs, and RREs influence power distribution in the solar atmosphere, revealing their significant impact on power halos and shadows observed in high-resolution solar data.

Contribution

It demonstrates that transient events can strongly affect power maps and the formation of power halos, highlighting their role in the dynamics of the quiet Sun's atmosphere.

Findings

Transients like RBEs and RREs dominate the formation of power halos.

Mottles do not significantly affect power suppression around 3 minutes.

Flows, waves, and shocks create a non-linear magnetohydrodynamic system.

Abstract

We have observed a quiet Sun region with the Swedish 1-meter Solar Telescope (SST) equipped with CRISP Imaging SpectroPolarimeter. High-resolution, high-cadence, H$\alpha$ line scanning images were taken to observe different layers of the solar atmosphere from the photosphere to upper chromosphere. We study the distribution of power in different period-bands at different heights. Power maps of the upper photosphere and the lower chromosphere show suppressed power surrounding the magnetic-network elements, known as "magnetic shadows". These also show enhanced power close to the photosphere, traditionally referred to as "power halos". The interaction between acoustic waves and inclined magnetic fields is generally believed to be responsible for these two effects. In this study we explore if small-scale transients can influence the distribution of power at different heights. We show that the presence of transients, like mottles, Rapid Blueshifted Excursions (RBEs) and Rapid Redshifted Excursions (RREs), can strongly influence the power-maps. The short and finite lifetime of these events strongly affects all powermaps, potentially influencing the observed power distribution. We show that Doppler-shifted transients like RBEs and RREs that occur ubiquitously, can have a dominant effect on the formation of the power halos in the quiet Sun. For magnetic shadows, transients like mottles do not seem to have a significant effect in the power suppression around 3 minutes and wave interaction may play a key role here. Our high cadence observations reveal that flows, waves and shocks manifest in presence of magnetic fields to form a non-linear magnetohydrodynamic system.