Utilization of design features of the particle telescope STEP-F and solar x-ray spectrophotometer SphinX for exploration of the Earth’s radiation belt properties

The radiation belts of the Earth and dynamics of high energy electron and proton fluxes in the magnetosphere in particular are still the target for intensive exploration by the scientific community. Quickly grown number of artificial Earth satellites including CubeSats around the Earth supports continuous improvement of the space weather forecast quality. As the charged space environment affects the wide aspects of human civilization life, the sustained monitoring of energized elementary particles is a current task. Different methods and sensors are developed to provide measurements of particle fluxes at the low Earth and geostationary orbits, at Lagrangian points and in the interplanetary space. Among them, there are silicon PIN, solid state, surface barrier detectors, organic and inorganic scintillation detectors, large area photodiodes, multi-pixelated silicon photomultipliers, etc. The gamma- and X-rays detectors are used rather often to study non-steady variations in magnetospheric particle fluxes because of a bremsstrahlung generation by precipitating subrelativistic electrons present in the upper layers of the atmosphere. We present specific features in constructing of the Satellite Telescope of Electrons and Protons STEP-F and the solar soft X-ray spectrophotometer SphinX that allowed for discovery of some interesting phenomena in radiation belts dynamics in 2009. Technical and scientific parameters of both instruments are demonstrated as well as approaches in respective development of sensors and electronics. We present some results of data processing like detection of three-belt structure of electron fluxes, the anisotropic character of particle motion in the outer and inner belts, lower limits of the energies for particle registration by the X-ray photometer.