Large-scale longitudinal intrusion of auroral electrons

In the Cosmos-261 and Cosmos-348 satellites rotating about the centre of masses, measurements of the pitch-angle distribution for auroral electrons in the energy range of 1-150 kev were made. Most of the measurements had to do with isotropic distributions corresponding to strong and weak diffusion. Cases of large-scale longitudinal distributions similar to those detected recently in the ISIS satellite were revealed. Longitudinal distributions were predominantly observed in the after-midnight and early-morning sectors (0-7 hr MLT) on closed of the polar light zone in the magnetic-quiet period or in the phase of recovery of a substorm in energy channels of 15 or 20-45 keV, and also at energies of 1.0 and 4.5 keV, and were practically nonexistent at energies exceeding 45 keV