Description
The study of coronal rain and other cool materials observed in the Sun’s upper atmosphere is becoming increasingly important given their connection to the fundamental mechanisms of coronal heating, flaring and eruption. The widely accepted formation mechanism of the phenomena is through concentrated footpoint heating of coronal loops. This heating leads to a cyclical process known as the Thermal Non-Equilibrium (TNE) cycle, resulting in an over-density of material, causing a subsequent rapid cooling of the plasma and it's coalescence into coronal rain. The drivers of this footpoint heating are still unknown though it is generally hypothesised that there may be a strong link to the local magnetic complexity.
We present a large-scale study of the solar atmosphere spanning five years of SDO observations to find any existing relationship between the magnetic complexity and the amount of cool material observed associated with a particular region of the Sun. We make use of the Polarity Inversion Measure (PIM) to quantify the magnetic complexity of an Active Region (AR) using HMI data. The amount of cool material present in this AR’s corona is then calculated with AIA 304~\AA\, using the RFit/Deep Filter algorithms that allow to identify the cool and hot emission within the passband. This process is then repeated for over 800 active regions. We observe a strong connection between magnetic complexity and the amount of cool material in the Sun’s atmosphere, and discuss the implications for solar and stellar studies of magnetic activity.
