Theory of incompressible MHD turbulence with scale-dependent alignment, anisotropy, and cross-helicity

Title: Theory of incompressible MHD turbulence with scale-dependent alignment, anisotropy, and cross-helicity

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Abstract

A theory of incompressible MHD turbulence with nonvanishing cross-helicity is derived based on two new observations from the Wind spacecraft. The first is the observation that the normalized cross-helicity {sigma}{sub c} is approximately scale-invariant throughout the inertial range. The second is the observation that the probablities p and q for velocity and magnetic field fluctuations to be positively or negatively aligned are also approximately scale-invariant. The theory extends the theory of Boldyrev (2006) to turbulence with nonvanishing cross-helicity assuming that the cascades of the two Elsasser energies are both in a state of critical balance.

Authors:

Podesta, John J ^[1]

Los Alamos National Laboratory

Publication Date:: 2009-01-01

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

Sponsoring Org.:: USDOE

OSTI Identifier:: 970029

Report Number(s):: LA-UR-09-05884; LA-UR-09-5884
TRN: US1000720

DOE Contract Number:: AC52-06NA25396

Resource Type:: Journal Article

Journal Name:: American Institute of Physics

Additional Journal Information:: Journal Name: American Institute of Physics

Country of Publication:: United States

Language:: English

Subject:: 70; 71; ALIGNMENT; ANISOTROPY; FLUCTUATIONS; MAGNETIC FIELDS; MAGNETOHYDRODYNAMICS; SOLAR WIND; TURBULENCE; VELOCITY

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                    Podesta, John J. Theory of incompressible MHD turbulence with scale-dependent alignment, anisotropy, and cross-helicity.  United States: N. p., 2009. 
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                    Podesta, John J. Theory of incompressible MHD turbulence with scale-dependent alignment, anisotropy, and cross-helicity.  United States.

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                    Podesta, John J. Thu .  
        "Theory of incompressible MHD turbulence with scale-dependent alignment, anisotropy, and cross-helicity".  United States.  https://www.osti.gov/servlets/purl/970029.

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@article{osti_970029,

  title        = {Theory of incompressible MHD turbulence with scale-dependent alignment, anisotropy, and cross-helicity},

  author       = {Podesta, John J},

  abstractNote = {A theory of incompressible MHD turbulence with nonvanishing cross-helicity is derived based on two new observations from the Wind spacecraft. The first is the observation that the normalized cross-helicity {sigma}{sub c} is approximately scale-invariant throughout the inertial range. The second is the observation that the probablities p and q for velocity and magnetic field fluctuations to be positively or negatively aligned are also approximately scale-invariant. The theory extends the theory of Boldyrev (2006) to turbulence with nonvanishing cross-helicity assuming that the cascades of the two Elsasser energies are both in a state of critical balance.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/970029},
  journal      = {American Institute of Physics},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {2009},

  month        = {1}

}

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