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On the relation between transition region network jets and coronal plumes

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 نشر من قبل Youqian Qi
 تاريخ النشر 2019
  مجال البحث فيزياء
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Both coronal plumes and network jets are rooted in network lanes. The relationship between the two, however, has yet to be addressed. For this purpose, we perform an observational analysis using images acquired with the Atmospheric Imaging Assembly (AIA) 171{AA} passband to follow the evolution of coronal plumes, the observations taken by the Interface Region Imaging Spectrograph (IRIS) slit-jaw 1330{AA} to study the network jets, and the line-of-sight magnetograms taken by the Helioseismic and Magnetic Imager (HMI) to overview the the photospheric magnetic features in the regions. Four regions in the network lanes are identified, and labeled ``R1--R4. We find that coronal plumes are clearly seen only in ``R1&R2 but not in ``R3&``R4, even though network jets abound in all these regions. Furthermore, while magnetic features in all these regions are dominated by positive polarity, they are more compact (suggesting stronger convergence) in ``R1&``R2 than that in ``R3&``R4. We develop an automated method to identify and track the network jets in the regions. We find that the network jets rooted in ``R1&``R2 are higher and faster than that in ``R3&``R4,indicating that network regions producing stronger coronal plumes also tend to produce more dynamic network jets. We suggest that the stronger convergence in ``R1&``R2 might provide a condition for faster shocks and/or more small-scale magnetic reconnection events that power more dynamic network jets and coronal plumes.



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