Intensity maps of MeV electrons and protons below the radiation belt

Global distributions of energetic electrons (0.19-3.2 MeV) and protons (0.64-35 MeV) are presented in the form of contour maps. The data were obtained by two identical energetic particle telescopes using ΔE × E solid state detectors on board the satellite OHZORA. The observed altitude range is 350-850 km, which is divided into three ranges for contour representation. Ten-degree meshes in longitude and latitude were used to obtain the intensity contours. A pitch angle distribution of J(α) = J(90) · sinⁿ α with n = 5 is assumed in order to get the intensity whose pitch angle is perpendicular to the geomagnetic line of force. In the map of the highest altitude region, a "ridge" extending from the South Atlantic Anomaly to the Northern Hemisphere exists above Mexico. A contour map in the B-L diagram is also presented. Here we can see some discrepancies at L = 1.1-1.5 from the radiation environment model of NSSDC. The data analyzed here were obtained during three years from February 1984 to January 1987. No geomagnetic activity was concerned.