Kinetic Scale Structure of Lowfrequency Waves and Fluctuations
Abstract
The dissipation of solar wind turbulence at kinetic scales is believed to be important for the heating of the corona and for accelerating the wind. The linear Vlasov kinetic theory is a useful tool for identifying various wave modes, including kinetic Alfvén, fast magnetosonic/whistler, and ionacoustic (or kinetic slow), and their possible roles in the dissipation. However, the kinetic mode structure in the vicinity of ioncyclotron modes is not clearly understood. The present paper aims to further elucidate the structure of these lowfrequency waves by introducing discrete particle effects through hybrid simulations and Klimontovich formalism of spontaneous emission theory. The theory and simulation of spontaneously emitted lowfrequency fluctuations are employed to identify and distinguish the detailed mode structures associated with ionBernstein modes versus quasimodes. The spontaneous emission theory and simulation also confirm the findings of the Vlasov theory in that the kinetic Alfvén waves can be defined over a wide range of frequencies, including the proton cyclotron frequency and its harmonics, especially for highbeta plasmas. This implies that these lowfrequency modes may play predominant roles even in the fully kinetic description of kinetic scale turbulence and dissipation despite the fact that cyclotron harmonic and Bernstein modes may also play importantmore »
 Authors:
 Institute for Physical Science and Technology, University of Maryland, College Park, MD 20742 (United States)
 NASA Goddard Space Flight Center, Heliophysics Science Division, Geospace Physics Laboratory, Mail Code 673, Greenbelt, MD 20771 (United States)
 Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Concepción, Concepción (Chile)
 Publication Date:
 OSTI Identifier:
 22663259
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Astrophysical Journal; Journal Volume: 845; Journal Issue: 1; 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; BERNSTEIN MODE; CYCLOTRON FREQUENCY; CYCLOTRON HARMONICS; CYCLOTRONS; EMISSION; FLUCTUATIONS; HIGHBETA PLASMA; ION ACOUSTIC WAVES; IONS; PROTONS; SIMULATION; SOLAR WIND; TURBULENCE; WHISTLERS
Citation Formats
López, Rodrigo A., Yoon, Peter H., Viñas, Adolfo F., and Araneda, Jaime A., Email: rlopezh@umd.edu, Email: yoonp@umd.edu. Kinetic Scale Structure of Lowfrequency Waves and Fluctuations. United States: N. p., 2017.
Web. doi:10.3847/15384357/AA7FEB.
López, Rodrigo A., Yoon, Peter H., Viñas, Adolfo F., & Araneda, Jaime A., Email: rlopezh@umd.edu, Email: yoonp@umd.edu. Kinetic Scale Structure of Lowfrequency Waves and Fluctuations. United States. doi:10.3847/15384357/AA7FEB.
López, Rodrigo A., Yoon, Peter H., Viñas, Adolfo F., and Araneda, Jaime A., Email: rlopezh@umd.edu, Email: yoonp@umd.edu. 2017.
"Kinetic Scale Structure of Lowfrequency Waves and Fluctuations". United States.
doi:10.3847/15384357/AA7FEB.
@article{osti_22663259,
title = {Kinetic Scale Structure of Lowfrequency Waves and Fluctuations},
author = {López, Rodrigo A. and Yoon, Peter H. and Viñas, Adolfo F. and Araneda, Jaime A., Email: rlopezh@umd.edu, Email: yoonp@umd.edu},
abstractNote = {The dissipation of solar wind turbulence at kinetic scales is believed to be important for the heating of the corona and for accelerating the wind. The linear Vlasov kinetic theory is a useful tool for identifying various wave modes, including kinetic Alfvén, fast magnetosonic/whistler, and ionacoustic (or kinetic slow), and their possible roles in the dissipation. However, the kinetic mode structure in the vicinity of ioncyclotron modes is not clearly understood. The present paper aims to further elucidate the structure of these lowfrequency waves by introducing discrete particle effects through hybrid simulations and Klimontovich formalism of spontaneous emission theory. The theory and simulation of spontaneously emitted lowfrequency fluctuations are employed to identify and distinguish the detailed mode structures associated with ionBernstein modes versus quasimodes. The spontaneous emission theory and simulation also confirm the findings of the Vlasov theory in that the kinetic Alfvén waves can be defined over a wide range of frequencies, including the proton cyclotron frequency and its harmonics, especially for highbeta plasmas. This implies that these lowfrequency modes may play predominant roles even in the fully kinetic description of kinetic scale turbulence and dissipation despite the fact that cyclotron harmonic and Bernstein modes may also play important roles in wave–particle interactions.},
doi = {10.3847/15384357/AA7FEB},
journal = {Astrophysical Journal},
number = 1,
volume = 845,
place = {United States},
year = 2017,
month = 8
}

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