000005416 001__ 5416
000005416 005__ 20210811213232.0
000005416 037__ $$aSEMIN-2021-0018
000005416 100__ $$aBerghmans, D.
000005416 245__ $$aFirst high resolution results from EUI: campfires and beyond
000005416 260__ $$c2021
000005416 269__ $$c2021-07-20
000005416 500__ $$aSeminar presented per teleconference
000005416 520__ $$aWe present results of the first high cadence image sequence of the Extreme Ultraviolet Imager (EUI) taken on 2020 May 30, when Solar Orbiter was 31.5 degrees in solar longitude separated from Earth & SDO, and at 0.56AU from the Sun. At this distance, the two-pixel spatial resolution of EUI’s High Resolution EUV Telescope (HRIEUV) was 400 km. HRIEUV observed a quiet Sun region and detected small localised brightenings, nicknamed ’campfires’, with length scales between 400 km and 4000 km and durations between 10 sec and 200 sec. The smallest and weakest of these HRIEUV brightenings have not been previously observed. Simultaneous observations from the EUI High-resolution Lyman-α telescope (HRILYA) do not show localised brightening events, but the locations of the HRIEUV events clearly correspond to the chromospheric network. Comparisons with simultaneous AIA images shows that most events can also be identified in the 17.1 nm, 19.3 nm, 21.1 nm, and 30.4 nm pass-bands of AIA, although they appear weaker and blurred. Our differential emission measure (DEM) analysis indicated coronal temperatures. We determined the height for a few of these campfires to be between 1 and 5 Mm above the photosphere. We interpret these events as a new extension to the flare-microflare-nanoflare family. Given their low height, the EUI ‘campfires’ could stand as a new element of the fine structure of the transition region-low corona, that is, as apexes of small-scale loops that undergo internal heating all the way up to coronal temperatures.
000005416 594__ $$aSTCE
000005416 773__ $$tAryabhatta Research Institute of Observational Sciences (ARIES), India
000005416 8560_ $$fdavid.berghmans@observatoire.be
000005416 980__ $$aSEMIN