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 process of fast magnetic reconnection supported by the formation ofplasmoid chains in the high Lundquist number ($S$) regime is investigated usinga recently developed adaptive finite-element magnetohydrodynamic (MHD) code. Weemploy a two-dimensional incompressible model with a set of reducedvisco-resistive MHD equations. The tilt instability setup is chosen to providea three-step mechanism, where two curved current sheets initially form on anAlfv\'enic time scale followed by a second phase of super-Alfv\'enic growth ofplasmoid chains for $S \ge S_c$ (Baty 2020). A third phase is reached where anensuing stochastic time-dependent reconnection regime with a fast time-averagedrate independent of $S$ is obtained. We reveal the multi-scale currentstructures during magnetic reconnection, where merging events of plasmoids giverise to monster plasmoids with shocks bounding the outflow regions. At highenough $S$ values (typically for $S \sim 100 S_c$), a dynamical Petschek-typereconnection is achieved with pairs of slow-mode shocks emanating from a smallcentral region containing a few plasmoids. Finally, we briefly discuss therelevance of our results to explain the flaring activity in solar corona andinternal disruptions in tokamaks.

Petschek-type reconnection in the high-Lundquist-number regime during nonlinear evolution on the tilt instability