English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Coronal upflows at the edges of active regions (AR), which are a possiblesource of slow solar wind, have been found to connect with dynamics in thetransition region. To infer at what scale transition region dynamics connect toAR upflows, we investigate the statistical properties of the small-scaledynamics in the transition region underneath the upflows at the edge of AR NOAA11934. With observations from the Interface Region Imaging Spectragraph (IRIS),we found that the Si IV 1403\,\AA\ Doppler map consists of numerousblue-shifted and red-shifted patches mostly with sizes less than 1\,$Mm^2$. Theblue-shifted structures in the transition region tend to be brighter than thered-shifted ones, but their nonthermal velocities have no significantdifference. With the SWAMIS feature tracking procedure, in IRIS slit-jaw1400\,\AA\ images we found that dynamic bright dots with an average size ofabout 0.3\,$Mm^2$ and lifetimes mostly less than 200\,s spread all over theregion. Most of the bright dots appear to be localised, without clear signatureof propagation of plasma to a long distance on the projection plane. Surge-likemotions with speeds about 15 km/s could be seen in some events at theboundaries of the upflow region, where the magnetic field appear to beinclined. We conclude that the transition region dynamics connecting to coronalupflows should occur in very fine scale, suggesting that the correspondingcoronal upflows should also be highly-structured. It is also plausible that thetransition region dynamics might just act as stimulation at the coronal basethat then drives the upflows in the corona.

Dynamics in the transition region beneath active region upflows viewed by IRIS