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Separatrices: The crux of reconnection

Published online by Cambridge University Press:  18 November 2014

Giovanni Lapenta*
Affiliation:
Department Wiskunde, Center for Mathematical Plasma Astrophysics, University of Leuven, KU Leuven, Belgium
Stefano Markidis
Affiliation:
High Performance Computing and Visualization Department, KTH Royal Institute of Technology, Stockholm, Sweden
Andrey Divin
Affiliation:
Swedish Institute of Space Physics, Uppsala, Sweden St. Petersburg State University, St. Petersburg, Russia
David Newman
Affiliation:
University of Colorado, Boulder, CO, USA
Martin Goldman
Affiliation:
University of Colorado, Boulder, CO, USA
*
Email address for correspondence: giovanni.lapenta@wis.kuleuven.be

Abstract

Magnetic reconnection is one of the key processes in astrophysical and laboratory plasmas: it is the opposite of a dynamo. Looking at energy, a dynamo transforms kinetic energy in magnetic energy while reconnection takes magnetic energy and returns it to its kinetic form. Most plasma processes at their core involve first storing magnetic energy accumulated over time and then releasing it suddenly. We focus here on this release. A key concept in analysing reconnection is that of the separatrix, a surface (line in 2D) that separates the fresh unperturbed plasma embedded in magnetic field lines not yet reconnected with the hotter exhaust embedded in reconnected field lines. In kinetic physics, the separatrices become a layer where many key processes develop. We present here new results relative to the processes at the separatrices that regulate the plasma flow, the energization of the species, the electromagnetic fields and the instabilities developing at the separatrices.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2014 

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References

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