Emerging Dimming as Coronal Heating Episodes

Emerging dimming occurs in isolated solar active regions (ARs) during the early stages of magnetic flux emergence. Observed by Atmospheric Imaging Assembly, it features a rapid decrease extreme-ultraviolet (EUV) emission 171 \r{A} channel images, and simultaneous increase 211 images. Here, we analyze coronal thermodynamic properties to probe its physical origin. We calculate time-dependent differential measures for sample 18 events between 2010 2012. The measure (EM) temperature range $5.7 \le \log_{10}T 5.9$ is well correlated with EM $6.2 6.4$ over eight orders magnitude. This suggests that plasma being heated from quiet-Sun, sub-MK 1-2 MK, more typical ARs. Potential field extrapolation indicates significant change local connectivity: region now linked newly emerged via longer loops. conclude emerging likely caused heating episodes, powered reconnection ambient fields.