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Title: Simulations of anti-parallel reconnection using a nonlocal heat flux closure

Abstract

The integration of kinetic effects in fluid models is important for global simulations of the Earth's magnetosphere. In particular, it has been shown that ion kinetics play a crucial role in the dynamics of large reconnecting systems, and that higher-order fluid moment models can account for some of these effects. Here, we use a ten-moment model for electrons and ions, which includes the off diagonal elements of the pressure tensor that are important for magnetic reconnection. Kinetic effects are recovered by using a nonlocal heat flux closure, which approximates linear Landau damping in the fluid framework. Moreover, the closure is tested using the island coalescence problem, which is sensitive to ion dynamics. We also demonstrate that the nonlocal closure is able to self-consistently reproduce the structure of the ion diffusion region, pressure tensor, and ion velocity without the need for fine-tuning of relaxation coefficients present in earlier models.

Authors:
ORCiD logo [1];  [1];  [1];  [2];  [2]
  1. Princeton Plasma Physics Lab. (PPPL) and Princeton Univ., NJ (United States). Center for Heliophysics, Dept. of Astrophysical Sciences
  2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Research Org.:
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Sponsoring Org.:
USDOE Office of Science (SC); National Science Foundation (NSF)
OSTI Identifier:
1398959
Alternate Identifier(s):
OSTI ID: 1374229
Grant/Contract Number:
AGS-0962698; AGS-1338944; PHY-1229408; NNH13AW51I; AC02-05CH11231; AC02-09CH11466
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 24; Journal Issue: 8; Journal ID: ISSN 1070-664X
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats

Ng, Jonathan, Hakim, Ammar, Bhattacharjee, A., Stanier, Adam, and Daughton, W. Simulations of anti-parallel reconnection using a nonlocal heat flux closure. United States: N. p., 2017. Web. doi:10.1063/1.4993195.
Ng, Jonathan, Hakim, Ammar, Bhattacharjee, A., Stanier, Adam, & Daughton, W. Simulations of anti-parallel reconnection using a nonlocal heat flux closure. United States. doi:10.1063/1.4993195.
Ng, Jonathan, Hakim, Ammar, Bhattacharjee, A., Stanier, Adam, and Daughton, W. Tue . "Simulations of anti-parallel reconnection using a nonlocal heat flux closure". United States. doi:10.1063/1.4993195.
@article{osti_1398959,
title = {Simulations of anti-parallel reconnection using a nonlocal heat flux closure},
author = {Ng, Jonathan and Hakim, Ammar and Bhattacharjee, A. and Stanier, Adam and Daughton, W.},
abstractNote = {The integration of kinetic effects in fluid models is important for global simulations of the Earth's magnetosphere. In particular, it has been shown that ion kinetics play a crucial role in the dynamics of large reconnecting systems, and that higher-order fluid moment models can account for some of these effects. Here, we use a ten-moment model for electrons and ions, which includes the off diagonal elements of the pressure tensor that are important for magnetic reconnection. Kinetic effects are recovered by using a nonlocal heat flux closure, which approximates linear Landau damping in the fluid framework. Moreover, the closure is tested using the island coalescence problem, which is sensitive to ion dynamics. We also demonstrate that the nonlocal closure is able to self-consistently reproduce the structure of the ion diffusion region, pressure tensor, and ion velocity without the need for fine-tuning of relaxation coefficients present in earlier models.},
doi = {10.1063/1.4993195},
journal = {Physics of Plasmas},
number = 8,
volume = 24,
place = {United States},
year = {Tue Aug 08 00:00:00 EDT 2017},
month = {Tue Aug 08 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
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