IRIS observational approach to the oscillatory and damping nature of network and internetwork chromosphere small-scale brightening (SSBs) and their unusual dynamical and morphological differences in different regions on the solar disk

TL;DR

This study investigates the oscillatory and damping properties of small-scale brightening events in different solar regions, revealing regional differences in their dynamics and damping behaviors, which are influenced by local plasma and magnetic conditions.

Contribution

It provides a comparative analysis of SSB oscillations and damping across various solar regions, highlighting regional differences and the influence of local plasma environments.

Findings

Internetwork SSBs in QS have lower damping time and higher Doppler velocities.

AAR internetwork SSBs show higher damping times and wider velocity ranges.

Most network SSBs in AAR are overdamped, while QS internetwork SSBs are overdamped and network SSBs are critically damped.

Abstract

One of the most exciting benefits of solar small-scale brightening is their oscillations, this study investigated the properties of small-scale brightening (SSBs) in different regions of the Sun and found that there are differences and similarities in the properties of oscillated and non-oscillated SSBs in different regions of the Sun, including quiet Sun (QS), the adjacent to active regions (AAR), and coronal hole (CH). The damping per period (Q-factor) and maximum Doppler velocity of SSBs varied depending on the region, with the less bright internetwork SSBs in QS having lower damping time (120 seconds) and higher maximum Doppler velocities (47 km/s) compared to the brighter network SSBs (with 216 seconds & 37 km/s, respectively), while in AAR, internetwork SSBs tend to have higher damping time (about of 220 seconds) and wider maximum Doppler velocity (10 to 140 km/s) ranges compared to network SSBs (130 seconds & 10 to 85 km/s). In CH, both types of SSBs show similar damping time (120 seconds), but internetwork SSBs tend to have higher maximum Doppler velocities (100 km/s) compared to network SSBs (85 km/s). Also, it was pointed out that the majority of network SSBs in AARs are in the overdamping mode, while in QS, internetwork SSBs demonstrate overdamping behavior and oscillated network SSBs exhibit critical damping behavior. It is important to bear in mind, however, that the physical mechanisms underlying the damping of SSBs may vary depending on the local plasma conditions and magnetic environment.