sufficiently long ($\sim 100$ days) time series that corresponded to the regions of the sky under consideration. The most significant linear regression coefficients were obtained for the channels 50-100 and 100- 200 keV ($\alpha \sim 0.04$ photon per particle). The effect of variations in the flux of charged particles in the channels 10-50 and 25-50 keV turned out to be weak. The $\alpha$ coefficient values were used to obtain the time series of count rates $N_{x}^{*} = N_{x} - \alpha N_{z}$ for subsequent analysis.

One of the main peculiarities of the GRIF experiment was the possibility of simultaneously monitoring all the principal components of background-producing emissions in the near-Earth space on “Mir” station orbits. Thus, the large-volume CsI(Tl) scintillator detectors of NEGA-1 instrument independently detected the local gamma-quanta ($\Delta E_{\gamma} = 0.15-50$ MeV, $S_{\gamma} \sim 250 cm^2$) and neutrons ($\Delta E_{n} > 20$ MeV, $S_{n} \sim 20 cm^2$) produced by the interaction of cosmic rays with the spacecraft material and the Earth’s atmosphere. The FON-1 electron detector (($\Delta E_{e} = 40-500$ keV) of high sensitivity was used to check the sporadic increases in X-ray flux attributable to bremsstrahlung from precipitating energetic magnetosphere electrons, which could simulate astrophysical phenomena (gamma-ray bursts, 