Abstract
In this paper, we consider the processes associated with the formation of a so-called foreshock region ahead of the front of a near-Earth collisionless shock wave. In the proposed theoretical model, ions in the ramp or the front of the shock wave are shown to be accelerated to significant energies. The physical conditions under which these ions accelerated in the shock front end up in front of the shock front and move away from it, as a result of which they are sometimes referred to the category of reflected ions, are found. It is concluded that this population of reflected energetic ions (they are most often called “longitudinal beams” or field-aligned beams) plays the main role in the formation of the ion foreshock boundary. The main properties of the longitudinal beams that follow from the considered model are compared with observational data obtained from a spacecraft.
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7. ACKNOWLEDGMENTS
The author thanks V.G. Eselevich for the attention to this work and useful discussions. The author is especially grateful to the reviewer for the very helpful comments.
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This work was supported within the framework of the Basic Research Program, II.16.
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Kichigin, G.N. Ionic Foreshock of a Near-Earth Shock Wave: Theoretical Model and Observational Data. Geomagn. Aeron. 61, 325–330 (2021). https://doi.org/10.1134/S0016793221030075
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DOI: https://doi.org/10.1134/S0016793221030075