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تسجيل مستخدم جديدHi-C 2.1 Observations of Small-Scale Miniature-Filament-Eruption-Like Cool Ejections in Active Region Plage
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We examine 172 Ang ultra-high-resolution images of a solar plage region from the Hi-C 2.1 (Hi-C) rocket flight of 2018 May 29. Over its five-minute flight, Hi-C resolves a plethora of small-scale dynamic features that appear near noise level in concurrent Solar Dynamics Observatory (SDO) Atmospheric Imaging Assembly (AIA) 171 Ang images. For ten selected events, comparisons with AIA images at other wavelengths and with the Interface Region Imaging Spectrograph (IRIS) images indicate that these features are cool (compared to the corona) ejections. Combining Hi-C 172 Ang, AIA 171 Ang, IRIS 1400 Ang, and H$alpha$, we see that these ten cool ejections are similar to the H$alpha$ dynamic fibrils and Ca ii anemone jets found in earlier studies. The front of some of our cool ejections are likely heated, showing emission in IRIS 1400 Ang. On average, these cool ejections have approximate widths: $3.2 pm 2.1$, (projected) maximum heights and velocities: $4.3 pm 2.5$ and $23 pm 6$ km/s, and lifetimes: $6.5 pm 2.4$ min. We consider whether these Hi-C features might result from eruptions of sub-minifilaments (smaller than the minifilaments that erupt to produce coronal jets). Comparisons with SDOs Helioseismic and Magnetic Imager (HMI) magnetograms do not show magnetic mixed-polarity neutral lines at these events bases, as would be expected for true scaled-do
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