Large-amplitude quasi-periodic pulsations as evidence of impulsive heating in hot transient loop systems detected in the EUV with SDO/AIA

TL;DR

This study detects large-amplitude quasi-periodic pulsations in hot coronal loops using SDO/AIA data, providing evidence for impulsive, localized heating events that match hydrodynamic models and offer insights into energy deposition in the solar corona.

Contribution

It presents observational evidence of pulsations caused by impulsive heating in coronal loops, aligning with hydrodynamic models and constraining heat deposition locations and durations.

Findings

Detection of pulsations in hot EUV coronal loops

Pulsations match hydrodynamic loop model predictions

Constraints on heating location and pulse duration

Abstract

Short heat pulses can trigger plasma pressure fronts inside closed magnetic tubes in the corona. The alternation of condensations and rarefactions from the pressure modes drive large-amplitude pulsations in the plasma emission. Here we show the detection of such pulsations along magnetic tubes that brighten transiently in the hot 94A EUV channel of SDO/AIA. The pulsations are consistent with those predicted by hydrodynamic loop modeling, and confirm pulsed heating in the loop system. The comparison of observations and model provides constraints on the heat deposition: a good agreement requires loop twisting and pulses deposited close to the footpoints with a duration of 0.5 min in one loop, and deposited in the corona with a duration of 2.5 min in another loop of the same loop system.