Particleincell simulation study of the scaling of asymmetric magnetic reconnection with inplane flow shear
Abstract
We investigate magnetic reconnection in systems simultaneously containing asymmetric (antiparallel) magnetic fields, asymmetric plasma densities and temperatures, and arbitrary inplane bulk flow of plasma in the upstream regions. Such configurations are common in the highlatitudes of Earth's magnetopause and in tokamaks. We investigate the convection speed of the Xline, the scaling of the reconnection rate, and the condition for which the flow suppresses reconnection as a function of upstream flow speeds. We use twodimensional particleincell simulations to capture the mixing of plasma in the outflow regions better than is possible in fluid modeling. We perform simulations with asymmetric magnetic fields, simulations with asymmetric densities, and simulations with magnetopauselike parameters where both are asymmetric. For flow speeds below the predicted cutoff velocity, we find good scaling agreement with the theory presented in Doss et al. [J. Geophys. Res. 120, 7748 (2015)]. Applications to planetary magnetospheres, tokamaks, and the solar wind are discussed.
 Authors:
 Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506 (United States)
 Department of Physics and Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20742 (United States)
 Publication Date:
 OSTI Identifier:
 22599936
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 8; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ASYMMETRY; COMPUTERIZED SIMULATION; CONVECTION; FLUIDS; MAGNETIC FIELDS; MAGNETIC RECONNECTION; MAGNETOPAUSE; PARTICLES; PLANETARY MAGNETOSPHERES; PLASMA DENSITY; SCALING; SHEAR; SOLAR WIND; TOKAMAK DEVICES; TWODIMENSIONAL CALCULATIONS; VELOCITY
Citation Formats
Doss, C. E., Cassak, P. A., Email: Paul.Cassak@mail.wvu.edu, and Swisdak, M.. Particleincell simulation study of the scaling of asymmetric magnetic reconnection with inplane flow shear. United States: N. p., 2016.
Web. doi:10.1063/1.4960324.
Doss, C. E., Cassak, P. A., Email: Paul.Cassak@mail.wvu.edu, & Swisdak, M.. Particleincell simulation study of the scaling of asymmetric magnetic reconnection with inplane flow shear. United States. doi:10.1063/1.4960324.
Doss, C. E., Cassak, P. A., Email: Paul.Cassak@mail.wvu.edu, and Swisdak, M.. 2016.
"Particleincell simulation study of the scaling of asymmetric magnetic reconnection with inplane flow shear". United States.
doi:10.1063/1.4960324.
@article{osti_22599936,
title = {Particleincell simulation study of the scaling of asymmetric magnetic reconnection with inplane flow shear},
author = {Doss, C. E. and Cassak, P. A., Email: Paul.Cassak@mail.wvu.edu and Swisdak, M.},
abstractNote = {We investigate magnetic reconnection in systems simultaneously containing asymmetric (antiparallel) magnetic fields, asymmetric plasma densities and temperatures, and arbitrary inplane bulk flow of plasma in the upstream regions. Such configurations are common in the highlatitudes of Earth's magnetopause and in tokamaks. We investigate the convection speed of the Xline, the scaling of the reconnection rate, and the condition for which the flow suppresses reconnection as a function of upstream flow speeds. We use twodimensional particleincell simulations to capture the mixing of plasma in the outflow regions better than is possible in fluid modeling. We perform simulations with asymmetric magnetic fields, simulations with asymmetric densities, and simulations with magnetopauselike parameters where both are asymmetric. For flow speeds below the predicted cutoff velocity, we find good scaling agreement with the theory presented in Doss et al. [J. Geophys. Res. 120, 7748 (2015)]. Applications to planetary magnetospheres, tokamaks, and the solar wind are discussed.},
doi = {10.1063/1.4960324},
journal = {Physics of Plasmas},
number = 8,
volume = 23,
place = {United States},
year = 2016,
month = 8
}

Effects of outofplane shear flows on asymmetric magnetic reconnect are investigated in a twodimensional (2D) hybrid model with an initial Harris sheet equilibrium. It is found that the outofplane flow with an inplane shear can significantly change the asymmetric reconnection process as well as the related geometry. The magnetic flux, outofplane magnetic field, inplane flow vorticity, plasma density, and the reconnection rate are discussed in detail. The results are in comparison with the cases without the shear flows to further understand the effect.

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