Statistical analysis of the pitch angle distribution of magnetospheric Solar protons during geomagnetic activity

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M. Scholer
G. Morfill
D. Hovestadt


The pitch angle distributions of energetic Solar protons in the pseudo-trapping region were used in order to examine magnetospheric processes. Temporal and spatial variations of these processes should give insight into the magnetospheric dynamics. Data from two instruments (viewing angle perpendicular and 45° with respect to the local geomagnetic field) on board the low altitude polar orbiting satellite GRS/Azur give a rough measure of the pitch angle distribution of energetic Solar protons (1.5<E<2.7 MeV) over the polar cap. For several Solar particle events the ratios of the counting rates of the two instruments were ordered according to invariant latitude, magnetic local time and geomagnetic activity. The geomagnetic activity was expressed by the time phase relative to the expansion of isolated substorms and the H-component of the magnetic field at a near midnight auroral station. Thus the analysis shows substorm-related effects on energetic particles in the pseudo-trapping region.

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Scholer, M., Morfill, G., & Hovestadt, D. (1974). Statistical analysis of the pitch angle distribution of magnetospheric Solar protons during geomagnetic activity. Journal of Geophysics, 40(1), 37-56. Retrieved from


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