This paper presents the results of the proton irradiation of silicon photomulipliers (SiPMs) by mono-energetic 170 MeV protons with fluence up to 4.6$times$10$^{9}$ particles/cm$^2$. In our work, three types of silicon photodetectors from Hamamatsu with areas 3$times$3 mm$^2$ and different subpixel sizes of 25$times$25 $mu$m$^2$, 50$times$50 $mu$m$^2$, and 75$times$75 $mu$m$^2$ were used. The changes in the SiPM dark count rate (DCR) spectrum before and after irradiation in temperatures in the range of 20 $^circ$C to -65 $^circ$C are presented. The influence of the DCR changes on the energy resolution of the 662 keV gamma line from the $^{137}$Cs for a non-irradiated GAGG:Ce (1$%$) scintillator is investigated. The time period of usability of the SiPM detector irradiated by protons in cosmic space was estimated.
Download