Particle discrimination in TeO2 bolometers

TeO2 crystals are used as bolometric detectors in experiments searching for the neutrinoless double beta decay. The extreme rarity of the studied signal requires an ultra low background level. The natural radioactivity of the materials represents for these experiments the main background source, in particular the component due to α particles. In this work, we present a possibility for particle discrimination in TeO2 bolometers using the Čerenkov radiation. The results show that we are able to measure the light produced by γ particles, which can be explained as due to Čerenkov emission. No light is detected from α particles, allowing the rejection of this background source. © Società Italiana di Fisica