Fast collisionless reconnection in electronpositron plasmas
Abstract
Magnetic reconnection in electronpositron (pair) plasmas is studied by twodimensional, electromagnetic, particleincell simulations. In pair plasmas, the Hall current does not appear because there is no scale separation between ion and electron motion. Simulations show that fast reconnection is realized in both nonrelativistic and relativistic regimes. It is demonstrated that the divergence of the electron and positron pressure tensors essentially plays the role of an effective collisionless resistivity in realizing fast reconnection. Since there is no Hall current in pair plasmas, there is no quadrupolar structure in the outofplane magnetic field. Particle acceleration by reconnection is investigated. Major sites of particle acceleration are the regions in the vicinity of X lines, where ultrarelativistic particles are generated by the reconnection electric field.
 Authors:
 Space Science Center and Center for Magnetic SelfOrganization, Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, New Hampshire 03824 (United States)
 Publication Date:
 OSTI Identifier:
 20975076
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 14; Journal Issue: 5; Other Information: DOI: 10.1063/1.2714020; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ACCELERATION; ELECTRIC FIELDS; ELECTRONS; MAGNETIC FIELDS; MAGNETIC RECONNECTION; MAGNETOHYDRODYNAMICS; PLASMA PRESSURE; PLASMA SIMULATION; POSITRONS; RELATIVISTIC PLASMA; RELATIVISTIC RANGE; TENSORS; TWODIMENSIONAL CALCULATIONS
Citation Formats
Bessho, Naoki, and Bhattacharjee, A. Fast collisionless reconnection in electronpositron plasmas. United States: N. p., 2007.
Web. doi:10.1063/1.2714020.
Bessho, Naoki, & Bhattacharjee, A. Fast collisionless reconnection in electronpositron plasmas. United States. doi:10.1063/1.2714020.
Bessho, Naoki, and Bhattacharjee, A. Tue .
"Fast collisionless reconnection in electronpositron plasmas". United States.
doi:10.1063/1.2714020.
@article{osti_20975076,
title = {Fast collisionless reconnection in electronpositron plasmas},
author = {Bessho, Naoki and Bhattacharjee, A.},
abstractNote = {Magnetic reconnection in electronpositron (pair) plasmas is studied by twodimensional, electromagnetic, particleincell simulations. In pair plasmas, the Hall current does not appear because there is no scale separation between ion and electron motion. Simulations show that fast reconnection is realized in both nonrelativistic and relativistic regimes. It is demonstrated that the divergence of the electron and positron pressure tensors essentially plays the role of an effective collisionless resistivity in realizing fast reconnection. Since there is no Hall current in pair plasmas, there is no quadrupolar structure in the outofplane magnetic field. Particle acceleration by reconnection is investigated. Major sites of particle acceleration are the regions in the vicinity of X lines, where ultrarelativistic particles are generated by the reconnection electric field.},
doi = {10.1063/1.2714020},
journal = {Physics of Plasmas},
number = 5,
volume = 14,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}

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