ИСТИНА

Ultra-low-frequency 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 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. The result of our work is the following: 1. The database for statistical and synoptic studies of the effect of the interplanetary magnetic field on the vibrational activity of magnetospheric cusps has been created. 2. The methodology is proposed for investigation the dependence of the magnetospheric cusps oscillations on the orientation of the foreshock. 3. The hypothesis of existence of the specific north-south asymmetry of magnetospheric cusps oscillations has been confirmed. Our work was partially supported by the Program 28 of the Presidium of RAS, and RFBR project 16-05-00056.