SCALAR AND VECTOR NONLINEAR DECAYS OF LOWFREQUENCY ALFVÉN WAVES
Abstract
We found several efficient nonlinear decays for Alfvén waves in the solar wind conditions. Depending on the wavelength, the dominant decay is controlled by the nonlinearities proportional to either scalar or vector products of wavevectors. The twomode decays of the pump MHD Alfvén wave into co and counterpropagating product Alfvén and slow waves are controlled by the scalar nonlinearities at long wavelengths ρ{sub i}{sup 2}k{sub 0⊥}{sup 2}ω{sub 0}/ω{sub ci}, threedimensional vector decays dominate generating outofplane product waves. The twomode decays dominate from MHD up to ion scales ρ {sub i} k {sub 0} ≅ 0.3; at shorter scales the onemode vector decays become stronger and generate only Alfvén product waves. In the solar wind the twomode decays have high growth rates >0.1ω{sub 0} and can explain the origin of slow waves observed at kinetic scales.
 Authors:
 Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China)
 SolarTerrestrial Centre of Excellence, Space Physics Division, Belgian Institute for Space Aeronomy, Ringlaan 3 Avenue Circulaire, B1180 Brussels (Belgium)
 Publication Date:
 OSTI Identifier:
 22364307
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Astrophysical Journal; Journal Volume: 799; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ALFVEN WAVES; MAGNETIC FIELDS; MAGNETOHYDRODYNAMICS; NONLINEAR PROBLEMS; PLASMA; SOLAR WIND; SUN; THREEDIMENSIONAL CALCULATIONS; TWODIMENSIONAL CALCULATIONS; WAVELENGTHS
Citation Formats
Zhao, J. S., Wu, D. J., Voitenko, Y., and De Keyser, J., Email: js_zhao@pmo.ac.cn. SCALAR AND VECTOR NONLINEAR DECAYS OF LOWFREQUENCY ALFVÉN WAVES. United States: N. p., 2015.
Web. doi:10.1088/0004637X/799/2/222.
Zhao, J. S., Wu, D. J., Voitenko, Y., & De Keyser, J., Email: js_zhao@pmo.ac.cn. SCALAR AND VECTOR NONLINEAR DECAYS OF LOWFREQUENCY ALFVÉN WAVES. United States. doi:10.1088/0004637X/799/2/222.
Zhao, J. S., Wu, D. J., Voitenko, Y., and De Keyser, J., Email: js_zhao@pmo.ac.cn. 2015.
"SCALAR AND VECTOR NONLINEAR DECAYS OF LOWFREQUENCY ALFVÉN WAVES". United States.
doi:10.1088/0004637X/799/2/222.
@article{osti_22364307,
title = {SCALAR AND VECTOR NONLINEAR DECAYS OF LOWFREQUENCY ALFVÉN WAVES},
author = {Zhao, J. S. and Wu, D. J. and Voitenko, Y. and De Keyser, J., Email: js_zhao@pmo.ac.cn},
abstractNote = {We found several efficient nonlinear decays for Alfvén waves in the solar wind conditions. Depending on the wavelength, the dominant decay is controlled by the nonlinearities proportional to either scalar or vector products of wavevectors. The twomode decays of the pump MHD Alfvén wave into co and counterpropagating product Alfvén and slow waves are controlled by the scalar nonlinearities at long wavelengths ρ{sub i}{sup 2}k{sub 0⊥}{sup 2}ω{sub 0}/ω{sub ci}, threedimensional vector decays dominate generating outofplane product waves. The twomode decays dominate from MHD up to ion scales ρ {sub i} k {sub 0} ≅ 0.3; at shorter scales the onemode vector decays become stronger and generate only Alfvén product waves. In the solar wind the twomode decays have high growth rates >0.1ω{sub 0} and can explain the origin of slow waves observed at kinetic scales.},
doi = {10.1088/0004637X/799/2/222},
journal = {Astrophysical Journal},
number = 2,
volume = 799,
place = {United States},
year = 2015,
month = 2
}

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