ИСТИНА

We study an event of simultaneous detection of EMIC waves in the H+ frequency band by the magnetospheric satellites RBSP-B and Arase/ERG in the evening MLT sector. Based on the data from these satellites, we infer the probable localization of the region of ion-cyclotron instability, the presence of which is further confirmed by the observation of IPDP by the Lovozero ground-based site at the same time in the magnetically conjugate region. The spatial distribution of precipitating energetic proton fluxes is analyzed according to the data of several conjugate flybys of NOAA POES low-orbiting satellites. The same spacecraft have observed relativistic electron precipitation that was most probably caused by the EMIC waves. The energies of precipitating energetic protons are compared with the results of calculations of the pitch-angle diffusion coefficients of energetic protons at low pitch-angles. Pitch-angle diffusion coefficient for relativistic electrons has also been calculated and compared with the observed precipitating flux