Modules of Cryogenic Scintillation Neutrino Detector with Energy Threshold below 500 eV

This work investigates scintillation modules of low-energy neutrino detector, read out by SiPMs. The study is focused the performance of SrI2(Eu) and CsI(pure) scintillators. The results showed a normalized light yield of 26 photoelectrons/keV for SrI2(Eu), while CsI(pure) at LN2 temperature yielded 23 photoelectrons/keV. Part of the study is dedicated to conducting detailed measurements of the SiPM array’s performance across a wide temperature range, from room down to liquid nitrogen temperatures. This was essential to quantify and mitigate the high Dark Current Rate (DCR), a major challenge for detecting rare events with low threshold.