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

3D numerical simulations of a horizontal magnetic flux tube emergence withdifferent twist are carried out in a computational domain spanning the upperlayers of the convection zone to the lower corona. We use the Oslo StaggeredCode to solve the full MHD equations with non-grey and non-LTE radiativetransfer and thermal conduction along the magnetic field lines. The emergenceof the magnetic flux tube input at the bottom boundary into a weakly magnetizedatmosphere is presented. The photospheric and chromospheric response isdescribed with magnetograms, synthetic images and velocity field distributions.The emergence of a magnetic flux tube into such an atmosphere results in variedatmospheric responses. In the photosphere the granular size increases when theflux tube approaches from below. In the convective overshoot region some 200kmabove the photosphere adiabatic expansion produces cooling, darker regions withthe structure of granulation cells. We also find collapsed granulation in theboundaries of the rising flux tube. Once the flux tube has crossed thephotosphere, bright points related with concentrated magnetic field, vorticity,high vertical velocities and heating by compressed material are found atheights up to 500km above the photosphere. At greater heights in the magnetizedchromosphere, the rising flux tube produces a cool, magnetized bubble thattends to expel the usual chromospheric oscillations. In addition the risingflux tube dramatically increases the chromospheric scale height, pushing thetransition region and corona aside such that the chromosphere extends up to 6Mmabove the photosphere. The emergence of magnetic flux tubes through thephotosphere to the lower corona is a relatively slow process, taking of order 1hour.

Twisted flux tube emergence from the convection zone to the corona