Performance of FBK high-density SiPMs in scintillation spectrometry

The aim of this work is to provide the characteristics of Fondazione Bruno Kessler (FBK) high-density SiPMs with an active area of 2.2×2.2 mm² (15×15 μm² single cell size) in gamma-ray spectrometry with LSO and CsI:Tl scintillators. The measurements presented in this work covered: measurements of the single photoelectron spectra, characteristics of the breakdown voltage versus temperature, verification of the excess noise factor, selection of the optimum operating voltage for energy resolution, verification of the linearity of the SiPM response for both used scintillators, verification of the number of photoelectrons and gamma-ray spectrometry for a wide range of X and gamma ray energies from 22.1 to 1408 keV. The results of energy resolution obtained with the FBK SiPMs readout and two different scintillators were compared to those obtained for the same scintillator with the XP2020Q PMT.