1990 Volume 42 Issue 6 Pages 753-761
Measurements of electron and ion beams and ion conics from the polar orbiting Viking satellite have been obtained in the cusp-cleft region. Frequencies of occurrence and relative frequencies of occurrence have been calculated in this region for studies of the distributions in MLT, Inv. Lat. and altitude during the period of study (March-June 1986). It was observed that the electron beams were more frequent in the dawn sector than in the dusk sector. These observations were similar and correlated to the ion conics and are compared in this study. On the other hand, an anticorrelation between electron- and ion-beams was also observed. The altitude dependence of the ion conics and electron beams showed a steep increase in frequency above 10000km up to the satellite apogee at about 13500km.