Abstract
A 3D problem of the formation of small-scale density caverns with a nonstationary electric field in the region of auroral electric currents and kinetic Alfvén wave currents is considered. It is shown that an excess of the electron current velocity over a certain critical value of their thermal velocity is a probable cause of cavern formation. Linear and nonlinear stages of the density cavern formation are considered, and their main parameters are estimated. In the case of comparatively strong magnetic fields, caverns can be formed with comparable longitudinal and transverse (with respect to the magnetic field) scales. The properties of parameters of small-scale density caverns and nonstationary electric field agree with well-known experimental data.
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Original Russian Text © P.A. Bespalov, V.G. Mizonova, 2015, published in Geomagnetizm i Aeronomiya, 2015, Vol. 55, No. 6, pp. 747–754.
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Bespalov, P.A., Mizonova, V.G. 3D model of small-scale density cavern formation in the region of auroral field-aligned currents. Geomagn. Aeron. 55, 723–729 (2015). https://doi.org/10.1134/S0016793215050047
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DOI: https://doi.org/10.1134/S0016793215050047