C44

Presentation Title:	Solar Active Region Coronal Jets: Hidden-onset Jets
Author(s):	Alphonse C. Sterling, Ronald L. Moore, & Navdeep K. Panesar

Abstract:

Solar quiet- and coronal-hole region coronal jets frequently clearly originate from erupting minifilaments,
but active-region jets often lack an obvious erupting-minifilament source. We observe a
coronal-jet-productive active region (AR), AR12824, over 2021 May 22 0–8 UT, primarily using
Solar Dynamics Observatory (SDO) Atmospheric Imaging Array (AIA) EUV images and
SDO/Helioseismic and Magnetic Imager magnetograms. Jets were concentrated in two locations
in the AR: on the south side and on the northwest side of the AR’s lone large sunspot. The
south-location jets are oriented so that we have a clear view of the jets’ origin low in the atmosphere:
their source is clearly minifilaments erupting from locations showing magnetic flux changes/cancelations.
After erupting a projected distance ~5′′ away from their origin site, the minifilaments erupt outward
onto far-reaching field as part of the jet’s spire, quickly losing their minifilament character. In contrast,
the northwest-location jets show no clear erupting minifilament, but the source site of those jets
are obscured along our line of sight by absorbing chromospheric material. EUV and magnetic data
indicate that the likely source sites were ~15′′ from where the we first see the jet spire; thus, an
erupting minifilament would likely lose its minifilament character before we first see the spire. We
conclude that such AR jets could work like non-AR jets, but the erupting-minifilament jet source is
often hidden by obscuring material. Another factor is that magnetic eruptions making some AR jets
carry only a harder-to-detect comparatively thin (∼1′′–2′′) minifilament “strand.” A full report appears
in Sterling et al. (2024, ApJ, 960, 109). This work was supported by the NASA Science Mission
Directorate's HSR and HGI programs, and through the NASA/MSFC Hinode Project.

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