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

We study 14 large solar jets observed in polar coronal holes. In EUV moviesfrom SDO/AIA, each jet appears similar to most X-ray jets and EUV jets thaterupt in coronal holes, but each is exceptional in that it goes higher thanmost, so high that it is observed in the outer corona beyond 2.2 RSun in imagesfrom the SOHO/LASCO/C2 coronagraph. From AIA He II 304 {\AA} movies andLASCO/C2 running-difference images of these high-reaching jets, we find: (1)the front of the jet transits the corona below 2.2 RSun at a speed typicallyseveral times the sound speed; (2) each jet displays an exceptionally largeamount of spin as it erupts; (3) in the outer corona, most of the jets displaymeasureable swaying and bending of a few degrees in amplitude; in three jetsthe swaying is discernibly oscillatory with a period of order 1 hour. Thesecharacteristics suggest that the driver in these jets is a magnetic-untwistingwave that is basically a large-amplitude (i.e., non-linear) torsional Alfvenwave that is put into the reconnected open field in the jet by interchangereconnection as the jet erupts. From the measured spinning and swaying weestimate that the magnetic-untwisting wave loses most of its energy in theinner corona below 2.2 RSun. We point out that the torsional waves observed inType-II spicules might dissipate in the corona in the same way as themagnetic-untwisting waves in our big jets and thereby power much of the coronalheating in coronal holes.

Magnetic Untwisting in Solar Jets that Go into the Outer Corona in Polar Coronal Holes