Wednesday

Active regions have been recently found to commonly host coronal loops that pulsate in EUV intensity with an incredibly precise period of several hours, lasting over several days. This feature is currently at odds with any 3D MHD modelling of active regions, since, for instance, it requires the debated concept of a loop to be well defined over a long period of time. Another common and enigmatic characteristic of active regions is the presence of material hundreds of times cooler in its atmosphere, falling along the loops in what is termed coronal rain. Both, EUV pulsations and coronal rain have been proposed as two aspects of the phenomenon of thermal non-equilibrium (TNE) in loops. TNE cycles are characterised by evaporation (heating) and condensation (cooling) phases, and are produced by highly stratified and quasi-steady, long duration heating in coronal loops. As such, they reflect specific spatiotemporal characteristics of the heating mechanism. In this work we report unique observations with SDO/AIA and SST/CRISP & CHROMIS that capture the extreme spatial scales covered by TNE processes. Within the same coronal loop bundle, we captured 6 hr-period coronal intensity pulsations in AIA, and coronal rain in chromospheric wavelengths of CRISP and CHROMIS, thus reinforcing the link between both phenomena. We present here the thermal analysis of the cycles as well as an extensive spectral characterisation of the rain clumps that allows us to measure precisely the chromosphere-corona solar atmospheric mass and energy cycle during TNE.