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

In space and astrophysical plasmas, turbulence is responsible fortransferring energy from large scales driven by violent events orinstabilities, to smaller scales where turbulent energy is ultimately convertedinto plasma heat by dissipative mechanisms. The nonlinear interaction betweencounterpropagating Alfven waves, denoted Alfven wave collisions, drives thisturbulent energy cascade, as recognized by early work with incompressiblemagnetohydrodynamic (MHD) equations. Recent work employing analyticalcalculations and nonlinear gyrokinetic simulations of Alfven wave collisions inan idealized periodic initial state have demonstrated the key properties thatstrong Alfven wave collisions mediate effectively the transfer of energy tosmaller perpendicular scales and self-consistently generate current sheets. Forthe more realistic case of the collision between two initially separated Alfvenwavepackets, we use a nonlinear gyrokinetic simulation to show here that thesekey properties persist: strong Alfven wavepacket collisions indeed facilitatethe perpendicular cascade of energy and give rise to current sheets.Furthermore, the evolution shows that nonlinear interactions occur only whilethe wavepackets overlap, followed by a clean separation of the wavepackets withstraight uniform magnetic fields and the cessation of nonlinear evolution inbetween collisions, even in the gyrokinetic simulation presented here whichresolves dispersive and kinetic effects beyond the reach of the MHD theory.

Nonlinear energy transfer and current sheet development in localized Alfven wavepacket collisions in the strong turbulence limit