Galactic gamma rays and the origin of cosmic-ray positrons in the diffusion model

The distribution of relativistic protons in the Galaxy is calculated in the frame of the diffusion model. These calculations are compared with those obtained from the γ-ray background observed on the satellites SAS 2 and COS B. The calculations have shown that in the energy range E_&gamma; < 10 GeV positrons are evidently produced in the galactic disk due to interaction of the diffusing proton-nuclear component with atomic hydrogen only. The positron spectrum for E_&gamma; > 10 GeV range cannot be described in the frame of this model and additional positron sources emitting hard-spectra particles are necessary. The calculations demonstrate that about 30% of the total γ-ray emission of the Galaxy is radiated by the halo in the energy range of 0.1 - 5 GeV. The other part of the emission in this energy range is radiated by the galactic disk.