Basing on measurements of cosmic rays at the worldwide network of stations, we calculate variations in the planetary system of geomagnetic cutoff rigidity for the 2015 June moderate geomagnetic storm. Using the axisymmetric model of the limited magnetosphere taking into account magnetopause currents and the ring current, we determine the distance to the subsolar point and the ring current radius, as well as the contribution of the ring current to variations in the geomagnetic cutoff rigidity and to the Dst index.
magnetosphere, current system, magnetic storm, cosmic rays
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