High-resolution Observations of Clustered Dynamic Extreme-Ultraviolet Bright Tadpoles near the Footpoints of Corona Loops

TL;DR

This study uses high-resolution EUV observations from Solar Orbiter and SDO/AIA to analyze clustered bright tadpoles near coronal loop footpoints, revealing their association with spicules and implications for coronal heating.

Contribution

It provides the first detailed stereoscopic measurements of CEBTs' altitudes and links their dynamics to spicule activity, offering new insights into small-scale coronal heating mechanisms.

Findings

CEBT altitudes range from ~1300 to 3300 km.

Majority of CEBTs are associated with Type I spicules.

Some CEBTs exhibit velocities exceeding 50 km/s.

Abstract

An extreme ultraviolet (EUV) close-up view of the Sun offers unprecedented detail of heating events in the solar corona. Enhanced temporal and spatial images obtained by the Solar Orbiter during its first science perihelion enabled us to identify clustered EUV bright tadpoles (CEBTs) occurring near the footpoints of coronal loops. Combining SDO/AIA observations, we determine the altitudes of six distinct CEBTs by stereoscopy, ranging from $\sim$1300 to 3300 km. We then notice a substantial presence of dark, cooler filamentary structures seemingly beneath the CEBTs, displaying periodic up-and-down motions lasting 3 to 5 minutes. This periodic behavior suggests an association of the majority of CEBTs with Type I spicules. Out of the ten selected CEBTs with fast downward velocity, six exhibit corrected velocities close to or exceeding 50 km $s^{-1}$. These velocities notably surpass the typical speeds of Type I spicules. We explore the generation of such velocities. It indicates that due to the previous limited observations of spicules in the EUV wavelengths, they may reveal novel observational features beyond our current understanding. Gaining insights into these features contributes to a better comprehension of small-scale coronal heating dynamics.