A comparison of the relative effect of the Earth’s Quasi-D.C. and A.C. electric field on Gradient Drift Waves in large-scale plasma structures in the polar regions

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Abstract

Radio signals traversing polar-cap plasma patches and other large-scale plasma structures in polar regions are prone to scintillation. This implies that irregularities in electron concentration often form within such structures. The current standard theory of the formation of such irregularities is that the primary Gradient Drift Instability drives a cascade from larger to smaller wavelengths that manifest as variations in electron concentration. The electric field can be described as the sum of a quasi-D.C. and an A.C. component. Whilst the effect of the quasi-D.C. component has been extensively investigated in theory and by modelling, the contribution of the A.C. component has been largely neglected. This paper investigates the relative contributions of both components, using data from the Dynamics Explorer 2 satellite. It concludes that the contribution of the A.C. electric field to irregularity growth cannot be neglected. This has consequences for our understanding of large-scale plasma structures in polar regions (and any associated radio scintillation) as the A.C. electric field component varies in all directions. Hence, it effect is not limited to the trailing edge of such structures, as it is for the quasi-D.C. component. This raises the need for new experimental and modelling investigations of these phenomena.
Original languageEnglish
JournalJournal of Geophysical Research: Space Physics
DOIs
Publication statusPublished - 20 Aug 2016

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polar regions
alternating current
direct current
gradients
electric fields
irregularities
scintillation
Dynamics Explorer 2 satellite
radio signals
trailing edges
polar caps
cascades
electrons
wavelengths

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title = "A comparison of the relative effect of the Earth’s Quasi-D.C. and A.C. electric field on Gradient Drift Waves in large-scale plasma structures in the polar regions",
abstract = "Radio signals traversing polar-cap plasma patches and other large-scale plasma structures in polar regions are prone to scintillation. This implies that irregularities in electron concentration often form within such structures. The current standard theory of the formation of such irregularities is that the primary Gradient Drift Instability drives a cascade from larger to smaller wavelengths that manifest as variations in electron concentration. The electric field can be described as the sum of a quasi-D.C. and an A.C. component. Whilst the effect of the quasi-D.C. component has been extensively investigated in theory and by modelling, the contribution of the A.C. component has been largely neglected. This paper investigates the relative contributions of both components, using data from the Dynamics Explorer 2 satellite. It concludes that the contribution of the A.C. electric field to irregularity growth cannot be neglected. This has consequences for our understanding of large-scale plasma structures in polar regions (and any associated radio scintillation) as the A.C. electric field component varies in all directions. Hence, it effect is not limited to the trailing edge of such structures, as it is for the quasi-D.C. component. This raises the need for new experimental and modelling investigations of these phenomena.",
author = "Ivan Astin and Cathryn Mitchell and Robert Burston",
year = "2016",
month = "8",
day = "20",
doi = "10.1002/2016JA022676",
language = "English",
journal = "Journal of Geophysical Research: Space Physics",
issn = "2169-9380",

}

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T1 - A comparison of the relative effect of the Earth’s Quasi-D.C. and A.C. electric field on Gradient Drift Waves in large-scale plasma structures in the polar regions

AU - Astin, Ivan

AU - Mitchell, Cathryn

AU - Burston, Robert

PY - 2016/8/20

Y1 - 2016/8/20

N2 - Radio signals traversing polar-cap plasma patches and other large-scale plasma structures in polar regions are prone to scintillation. This implies that irregularities in electron concentration often form within such structures. The current standard theory of the formation of such irregularities is that the primary Gradient Drift Instability drives a cascade from larger to smaller wavelengths that manifest as variations in electron concentration. The electric field can be described as the sum of a quasi-D.C. and an A.C. component. Whilst the effect of the quasi-D.C. component has been extensively investigated in theory and by modelling, the contribution of the A.C. component has been largely neglected. This paper investigates the relative contributions of both components, using data from the Dynamics Explorer 2 satellite. It concludes that the contribution of the A.C. electric field to irregularity growth cannot be neglected. This has consequences for our understanding of large-scale plasma structures in polar regions (and any associated radio scintillation) as the A.C. electric field component varies in all directions. Hence, it effect is not limited to the trailing edge of such structures, as it is for the quasi-D.C. component. This raises the need for new experimental and modelling investigations of these phenomena.

AB - Radio signals traversing polar-cap plasma patches and other large-scale plasma structures in polar regions are prone to scintillation. This implies that irregularities in electron concentration often form within such structures. The current standard theory of the formation of such irregularities is that the primary Gradient Drift Instability drives a cascade from larger to smaller wavelengths that manifest as variations in electron concentration. The electric field can be described as the sum of a quasi-D.C. and an A.C. component. Whilst the effect of the quasi-D.C. component has been extensively investigated in theory and by modelling, the contribution of the A.C. component has been largely neglected. This paper investigates the relative contributions of both components, using data from the Dynamics Explorer 2 satellite. It concludes that the contribution of the A.C. electric field to irregularity growth cannot be neglected. This has consequences for our understanding of large-scale plasma structures in polar regions (and any associated radio scintillation) as the A.C. electric field component varies in all directions. Hence, it effect is not limited to the trailing edge of such structures, as it is for the quasi-D.C. component. This raises the need for new experimental and modelling investigations of these phenomena.

UR - http://dx.doi.org/10.1002/2016JA022676

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JO - Journal of Geophysical Research: Space Physics

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SN - 2169-9380

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