TWOFLUID MAGNETOHYDRODYNAMIC SIMULATIONS OF RELATIVISTIC MAGNETIC RECONNECTION
Abstract
We investigate the largescale evolution of a relativistic magnetic reconnection in an electronpositron pair plasma by a relativistic twofluid magnetohydrodynamic (MHD) code. We introduce an interspecies friction force as an effective resistivity to dissipate magnetic fields. We demonstrate that magnetic reconnection successfully occurs in our twofluid system, and that it involves Petschektype bifurcated current layers in a later stage. We further observe a quasisteady evolution thanks to an open boundary condition, and find that the Petschektype structure is stable over the long time period. Simulation results and theoretical analyses exhibit that the Petschek outflow channel becomes narrower when the reconnection inflow contains more magnetic energy, as previously claimed. Meanwhile, we find that the reconnection rate goes up to {approx}1 in extreme cases, which is faster than previously thought. The role of the resistivity, implications for reconnection models in the magnetically dominated limit, and relevance to kinetic reconnection works are discussed.
 Authors:
 NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States), Email: Seiji.Zenitani1@nasa.gov
 Publication Date:
 OSTI Identifier:
 21300674
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Astrophysical Journal; Journal Volume: 696; Journal Issue: 2; Other Information: DOI: 10.1088/0004637X/696/2/1385; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; ASTROPHYSICS; BOUNDARY CONDITIONS; EVOLUTION; MAGNETIC FIELDS; MAGNETIC RECONNECTION; MAGNETOHYDRODYNAMICS; PLASMA; POSITRONS; RELATIVISTIC RANGE; SIMULATION
Citation Formats
Zenitani, Seiji, Hesse, Michael, and Klimas, Alex. TWOFLUID MAGNETOHYDRODYNAMIC SIMULATIONS OF RELATIVISTIC MAGNETIC RECONNECTION. United States: N. p., 2009.
Web. doi:10.1088/0004637X/696/2/1385; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA).
Zenitani, Seiji, Hesse, Michael, & Klimas, Alex. TWOFLUID MAGNETOHYDRODYNAMIC SIMULATIONS OF RELATIVISTIC MAGNETIC RECONNECTION. United States. doi:10.1088/0004637X/696/2/1385; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA).
Zenitani, Seiji, Hesse, Michael, and Klimas, Alex. Sun .
"TWOFLUID MAGNETOHYDRODYNAMIC SIMULATIONS OF RELATIVISTIC MAGNETIC RECONNECTION". United States.
doi:10.1088/0004637X/696/2/1385; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA).
@article{osti_21300674,
title = {TWOFLUID MAGNETOHYDRODYNAMIC SIMULATIONS OF RELATIVISTIC MAGNETIC RECONNECTION},
author = {Zenitani, Seiji and Hesse, Michael and Klimas, Alex},
abstractNote = {We investigate the largescale evolution of a relativistic magnetic reconnection in an electronpositron pair plasma by a relativistic twofluid magnetohydrodynamic (MHD) code. We introduce an interspecies friction force as an effective resistivity to dissipate magnetic fields. We demonstrate that magnetic reconnection successfully occurs in our twofluid system, and that it involves Petschektype bifurcated current layers in a later stage. We further observe a quasisteady evolution thanks to an open boundary condition, and find that the Petschektype structure is stable over the long time period. Simulation results and theoretical analyses exhibit that the Petschek outflow channel becomes narrower when the reconnection inflow contains more magnetic energy, as previously claimed. Meanwhile, we find that the reconnection rate goes up to {approx}1 in extreme cases, which is faster than previously thought. The role of the resistivity, implications for reconnection models in the magnetically dominated limit, and relevance to kinetic reconnection works are discussed.},
doi = {10.1088/0004637X/696/2/1385; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA)},
journal = {Astrophysical Journal},
number = 2,
volume = 696,
place = {United States},
year = {Sun May 10 00:00:00 EDT 2009},
month = {Sun May 10 00:00:00 EDT 2009}
}

The nonlinear evolution of relativistic magnetic reconnection in sheared magnetic configuration (with a guide field) is investigated by using twodimensional relativistic twofluid simulations. Relativistic guide field reconnection features the charge separation and the guide field compression in and around the outflow channel. As the guide field increases, the composition of the outgoing energy changes from enthalpydominated to Poyntingdominated. The inertial effects of the twofluid model play an important role to sustain magnetic reconnection. Implications for the singlefluid magnetohydrodynamic approach and the physics models of relativistic reconnection are briefly addressed.

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