Physics, mathematics, and technology

2014 Issue №4

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Dipolarization of the earth magnetic field and charge particles precipitation from the magnetic flux tube



During the expansion phase of the substorm in the nightside magnetosphere enhancement of the magnetic field and decrease the plasma pressure is observed simultaneously. Enhancement of the magnetic field is recorded at first in the tail of the magnetosphere, and then at more closer distances from the Earth. This process takes a few minutes and covers the region in the magnetosphere of 10 Earth radii. One of possible explanations of this phenomenon is associated with cooling magnetic flux tubes caused by the precipitation of the energetic particles in the ionosphere. We have made evaluation of the effectiveness of this mechanism.


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