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 Tools annual

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 monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Context. Ubiquitous small-scale vortical motions are seen to occur in thesolar atmosphere both in simulations and observations. They are thought to playa significant role in the local heating of the quiet chromosphere and corona.In a previous paper, we proposed a new method for the automated identificationof vortices based on the accurate estimation of curvature centers; this methodwas implemented in the SWIRL algorithm. Aims. We aim to assess theapplicability of the SWIRL algorithm to self-consistent numerical simulationsof the solar atmosphere. The highly turbulent and dynamical solar flow poses achallenge to any vortex-detection method. We also conduct a statisticalanalysis of the properties and characteristics of photospheric andchromospheric small-scale swirling motions in numerical simulations. Methods.We applied the SWIRL algorithm to realistic, three-dimensional, radiative,magneto-hydrodynamical simulations of the solar atmosphere carried out with theCO5BOLD code. In order to achieve statistical validity, we analyzed 30 timeinstances of the simulation covering 2 h of physical time. Results. The SWIRLalgorithm accurately identified most of the photospheric and chromosphericswirls, which are perceived as spiraling instantaneous streamlines of thehorizontal component of the flow. Part of the identified swirls formthree-dimensional coherent structures that are generally rooted in magneticallydominated intergranular lanes and extend vertically into the chromosphericlayers. From a statistical analysis, we find that the average number densitiesof swirls in the photosphere and chromosphere are 1 Mm-2 and 4 Mm-2,respectively, while the average radius is 50 - 60 km throughout the simulatedatmosphere. We also find an approximately linear correlation between therotational speed of chromospheric swirls and the local Alfv\'en speed.(Abridged)

Innovative and automated method for vortex identification. II. Application to numerical simulations of the solar atmosphere