Comprehensive analysis of a filament-embedding solar active region at different stages of evolution

In this work, we present a comprehensive study for a filament-embedding active region as determined from observations from multiple facilities including the Chinese H alpha Solar Explorer. We find three types of dynamic features that correspond to different thermal and magnetic properties, i.e., the overlying loops-1 MK cool loops, the moss region-2-3 MK hot loops' footprints, and the sigmoidal filament.

The overlying cool loops, which have a potential field, always show Doppler blueshifts at the east footprint and Doppler redshifts at the west, indicating a pattern of "siphon flow." The moss-brightening regions, which sustain the hot loops that have a moderate sheared field, always show downward Doppler redshifts at the chromosphere, which could be a signature of plasma condensing into the inner region adjacent to the filament.