skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Structure and Dynamics of Three-Dimensional Magnetotail Reconnection

Abstract

In this study, we have used a global magnetohydrodynamic simulation and embedded particle-in-cell (PIC) simulation to analyze magnetotail reconnection in and near the electron diffusion region (EDR). Results from the magnetohydrodynamic simulation were used to set the initial and boundary conditions for the large-scale implicit PIC simulation. We examined proxies for the EDR (the nongyrotropy of the electron distribution function, slippage, and the nonideal terms in Ohm's law and the work done [J·E'] in the electron frame). The reconnection was well organized by the B x = 0 surface. All of the proxies gave false positive values but together, along with the magnetic field B z component and calculations of magnetic field lines, we were able to locate the EDR. Three of the proxies (the slippage, the nonideal terms in Ohm's law, and agyrotropy) give consistent results in the EDR. The EDR is structured and time dependent. Multiple EDRs aligned roughly parallel to the X axis extended from X ~ -31R E to X ~ -38R E with structure in the Y direction. There are regions with both J·E' < 0 and J·' > 0. Wave-like behavior with a scale of ~0.5R E or 2–3d i develops in the reconnectedmore » plasma sheet. The structure is closely related to strong electron flows in the YZ plane and to the density gradient at the outer edge of the plasma sheet. Finally, these results are consistent with expectations for the lower hybrid drift instability coupled with a shear-type instability such as the Kelvin-Helmholtz instability. Similar results were found in a Harris sheet PIC simulation.« less

Authors:
ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [3];  [1]; ORCiD logo [1]; ORCiD logo [4]
  1. Univ. of California, Los Angeles, CA (United States)
  2. Katholicke Univ., Leuven (Belgium)
  3. Univ. of California, Los Angeles, CA (United States); West Virginia Univ., Morgantown, WV (United States)
  4. Space Science Institute, Boulder, CO (United States); NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States)
Publication Date:
Research Org.:
Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). National Energy Research Scientific Computing Center (NERSC)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1544195
Alternate Identifier(s):
OSTI ID: 1479508
Grant/Contract Number:  
AC02-05CH11231; 80NSSC17K0014; AGS-1450864; IAP P7/08 CHARM; NNX08AO48G; 80GSFC17C0018
Resource Type:
Accepted Manuscript
Journal Name:
Journal of Geophysical Research. Space Physics
Additional Journal Information:
Journal Volume: 123; Journal Issue: 10; Journal ID: ISSN 2169-9380
Publisher:
American Geophysical Union
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; reconnection; MHD and kinetic simulation; magnetotail

Citation Formats

Walker, Raymond J., Lapenta, Giovanni, Liang, Haoming, Berchem, Jean, El-Alaoui, Mostafa, and Goldstein, Melvyn L. Structure and Dynamics of Three-Dimensional Magnetotail Reconnection. United States: N. p., 2018. Web. doi:10.1029/2018JA025509.
Walker, Raymond J., Lapenta, Giovanni, Liang, Haoming, Berchem, Jean, El-Alaoui, Mostafa, & Goldstein, Melvyn L. Structure and Dynamics of Three-Dimensional Magnetotail Reconnection. United States. doi:10.1029/2018JA025509.
Walker, Raymond J., Lapenta, Giovanni, Liang, Haoming, Berchem, Jean, El-Alaoui, Mostafa, and Goldstein, Melvyn L. Sat . "Structure and Dynamics of Three-Dimensional Magnetotail Reconnection". United States. doi:10.1029/2018JA025509. https://www.osti.gov/servlets/purl/1544195.
@article{osti_1544195,
title = {Structure and Dynamics of Three-Dimensional Magnetotail Reconnection},
author = {Walker, Raymond J. and Lapenta, Giovanni and Liang, Haoming and Berchem, Jean and El-Alaoui, Mostafa and Goldstein, Melvyn L.},
abstractNote = {In this study, we have used a global magnetohydrodynamic simulation and embedded particle-in-cell (PIC) simulation to analyze magnetotail reconnection in and near the electron diffusion region (EDR). Results from the magnetohydrodynamic simulation were used to set the initial and boundary conditions for the large-scale implicit PIC simulation. We examined proxies for the EDR (the nongyrotropy of the electron distribution function, slippage, and the nonideal terms in Ohm's law and the work done [J·E'] in the electron frame). The reconnection was well organized by the Bx = 0 surface. All of the proxies gave false positive values but together, along with the magnetic field Bz component and calculations of magnetic field lines, we were able to locate the EDR. Three of the proxies (the slippage, the nonideal terms in Ohm's law, and agyrotropy) give consistent results in the EDR. The EDR is structured and time dependent. Multiple EDRs aligned roughly parallel to the X axis extended from X ~ -31RE to X ~ -38RE with structure in the Y direction. There are regions with both J·E' < 0 and J·' > 0. Wave-like behavior with a scale of ~0.5RE or 2–3di develops in the reconnected plasma sheet. The structure is closely related to strong electron flows in the YZ plane and to the density gradient at the outer edge of the plasma sheet. Finally, these results are consistent with expectations for the lower hybrid drift instability coupled with a shear-type instability such as the Kelvin-Helmholtz instability. Similar results were found in a Harris sheet PIC simulation.},
doi = {10.1029/2018JA025509},
journal = {Journal of Geophysical Research. Space Physics},
number = 10,
volume = 123,
place = {United States},
year = {2018},
month = {9}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 1 work
Citation information provided by
Web of Science

Save / Share: