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arXiv · 1805.02256

The IMF impact on the ULF oscillations in the magnetospheric polar cusps

A. V. Guglielmi·O. V. Kozyreva
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Abstract

Ultra-low-frequency (ULF) oscillations of the magnetospheric cusps are observed permanently in the near-mid sector of auroral oval in the form of so-called IPCL. In this paper, we posed the question: do electromagnetic waves incident on cusp from the foreshock (it is a special region of cosmic plasma existing before the front of the magnetosphere) affect the IPCL regime? We have proposed a method of experimental investigation, which is based on the idea of the foreshock position dependence on the interplanetary magnetic field (IMF) orientation. A hypothesis has been put forward on the existence of a specific effect of the IPCL north-south asymmetry. We tested our hypothesis using IPCL observation data from the Hornsund (Spitsbergen) and Davis (Antarctica) observatories. We found confirmation of the hypothesis at a high confidence level of statistical significance. Keywords: magnetosphere, ultra-low-frequency oscillations, north-south asymmetry.

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A. V. Guglielmi, O. V. Kozyreva. 2018-05-06. The IMF impact on the ULF oscillations in the magnetospheric polar cusps. https://arxiv.org/abs/1805.02256

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