We have two student papers out on arXiv today! The first is from Anna Payne (arxiv.org/abs/2103.09087). We studied EUV dimming associated with flux emergence, which is termed “emerging dimming”. We used AIA and HMI data to probe its origin. 1/5 
The dimming occurs only in 171 A, and coincides with brightening in 211 A. We performed DEM analysis on 18 events. The amount of sub-MK plasma decreases, and the 1-2 MK plasma increases. The changes are correlated over 8 orders of magnitude! 2/5
We also look at the magnetic fields. The quiet-Sun photospheric field in the dimming region doesn’t change much. However, a potential field model shows that they are now connected to the emerged active region. 3/5
Because all regions are quiet-Sun like with no access to open field, we think the dimming is caused by cool plasma being heated and moving out of the 171 A temperature range rather than outflows. 4/5
We conclude that reconnection between the quiet Sun and emerging AR heats the corona and creates the “emerging dimming”. This seems somewhat different from the dark moats around well formed ARs in 171 A. 5/5
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