Abstract
For southward Interplanetary Magnetic Field (IMF), the He2+/H+ density ratio in the cusp can be several times higher than the ratio in the solar wind. Proceeding poleward from the equatorial edge of the cusp, the ratio first increases to well above the solar wind value, then decreases to values at or below that in the solar wind. Superposed on this overall change are more rapid (2–3 minute) variations in the density ratio. A model for the magnetosheath ion distributions is used to explain both the overall change and the variations in the cusp density ratio.
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© 1998 Springer Science+Business Media Dordrecht
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Fuselier, S.A., Shelley, E.G., Peterson, W.K., Lennartsson, O.W. (1998). Solar Wind He2+ and H+ Distributions in the Cusp for Southward IMF. In: Moen, J., Egeland, A., Lockwood, M. (eds) Polar Cap Boundary Phenomena. NATO ASI Series, vol 509. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-5214-3_6
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DOI: https://doi.org/10.1007/978-94-011-5214-3_6
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