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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The temporal variation of the horizontal velocity in subsurface layersbeneath three different types of active regions is studied using the techniqueof ring diagrams. In this study, we select active regions (ARs) 10923, 10930,10935 from three consecutive Carrington rotations: AR 10930 contains afast-rotating sunspot in a strong emerging active region while other two havenon-rotating sunspots with emerging flux in AR 10923 and decaying flux in AR10935. The depth range covered is from the surface to about 12 Mm. In order tominimize the influence of systematic effects, the selection of active and quietregions is made so that these were observed at the same heliographic locationson the solar disk. We find a significant variation in both components of thehorizontal velocity in active regions as compared to quiet regions. Themagnitude is higher in emerging-flux regions than in the decaying-flux region,in agreement with earlier findings. Further, we clearly see a significanttemporal variation in depth profiles of both zonal and meridional flowcomponents in AR 10930, with the variation in the zonal component being morepronounced. We also notice a significant influence of the plasma motion inareas closest to the rotating sunspot in AR 10930 while areas surrounding thenon-rotating sunspots in all three cases are least affected by the presence ofthe active region in their neighborhood.

Subsurface Flows in and Around Active Regions with Rotating and Non-rotating Sunspots