Connecting Global Measures of 3D Magnetic Reconnection to Local Kinetic Physics

Daughton, William Scott

Title: Connecting Global Measures of 3D Magnetic Reconnection to Local Kinetic Physics

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Abstract

After giving the motivation for the work, slides present the topic under the following headings: Description of LAPD experiment; Actual simulation setup; Simple kinetic theory of ined-tied tearing; Diagnostics to characterizing 3D reconnection; Example #1 - short-tied system; and Example #2 - long line-tied system. Colorful simulations are shown for quasipotential vs field line exponentiation, field line integrated Ohms Law, and correlation with agyrotopy & energy conversion for example #1; and evolution of current density for largest case, field exponentiation vs quasi-potential, and time evolution of magnetic field lines for example #2. To satisfy line-tied boundary conditions, there is need for superposition of oblique modes--the simple two-mode approximation works surprisingly well. For force-free layers with b_g >1, the fastest growing periodic modes are oblique with k_xλ ~0.5. This implies a minimum length of L_y > 2πλb_g. There are strong correlations between σ → Ξ → A_0e (observable with spacecraft). Electron pressure tensor is the dominant non-ideal term.

Authors:

Daughton, William Scott ^[1]

Los Alamos National Laboratory

Publication Date:: Thu Jul 16 00:00:00 EDT 2015

Research Org.:: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

Sponsoring Org.:: USDOE Laboratory Directed Research and Development (LDRD) Program

OSTI Identifier:: 1196165

Report Number(s):: LA-UR-15-25445

DOE Contract Number:: AC52-06NA25396

Resource Type:: Conference

Resource Relation:: Conference: Plasma Energization: Exchanges between Fluid and Kinetic Scales ; 2015-05-04 - 2015-05-06 ; Los Alamos, New Mexico, United States, Melbourne (Australia), 19-25 Apr 2015

Country of Publication:: United States

Language:: English

Subject:: 79 ASTRONOMY AND ASTROPHYSICS; Astronomy and Astrophysics

Citation Formats


                    Daughton, William Scott. Connecting Global Measures of 3D Magnetic Reconnection to Local Kinetic Physics.  United States: N. p., 2015. 
        Web.

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                    Daughton, William Scott. Connecting Global Measures of 3D Magnetic Reconnection to Local Kinetic Physics.  United States.

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                    Daughton, William Scott. 2015.  
        "Connecting Global Measures of 3D Magnetic Reconnection to Local Kinetic Physics".  United States.  https://www.osti.gov/servlets/purl/1196165.

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@article{osti_1196165,

  title        = {Connecting Global Measures of 3D Magnetic Reconnection to Local Kinetic Physics},

  author       = {Daughton, William Scott},

  abstractNote = {After giving the motivation for the work, slides present the topic under the following headings: Description of LAPD experiment; Actual simulation setup; Simple kinetic theory of ined-tied tearing; Diagnostics to characterizing 3D reconnection; Example #1 - short-tied system; and Example #2 - long line-tied system. Colorful simulations are shown for quasipotential vs field line exponentiation, field line integrated Ohms Law, and correlation with agyrotopy & energy conversion for example #1; and evolution of current density for largest case, field exponentiation vs quasi-potential, and time evolution of magnetic field lines for example #2. To satisfy line-tied boundary conditions, there is need for superposition of oblique modes--the simple two-mode approximation works surprisingly well. For force-free layers with bg >1, the fastest growing periodic modes are oblique with kxλ ~0.5. This implies a minimum length of Ly > 2πλbg. There are strong correlations between σ → Ξ → A0e (observable with spacecraft). Electron pressure tensor is the dominant non-ideal term.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/1196165},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Thu Jul 16 00:00:00 EDT 2015},

  month        = {Thu Jul 16 00:00:00 EDT 2015}

}

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