1 research outputs found
Complete event-by-event α/γ(β) separation in a full-size TeO2 CUORE bolometer by simultaneous heat and light detection
The CUORE project began recently a search for neutrinoless double-beta decay () of Te with a (1 ton) TeO bolometer array. In this experiment, the background suppression relies essentially on passive shielding, material radiopurity and anti-coincidences. The lack of particle identification in CUORE makes decays at the detector surface the dominant background, at the level of 0.01 counts/(keV kg y) in the region of interest (-value of of the order of 2.5 MeV). In the present work we demonstrate, for the first time with a CUORE-size (555 cm) TeO bolometer and using the same technology as CUORE for the readout of the bolometric signals, an efficient particle discrimination (99.9\%) with a high acceptance of the signal (about 96\%). This unprecedented result was possible thanks to the superior performance (10 eV RMS baseline noise) of a Neganov-Luke-assisted germanium bolometer used to detect a tiny (70 eV) light signal dominated by ()-induced Cherenkov radiation in the TeO detector. The obtained results represent a major breakthrough towards the TeO-based version of CUPID, a ton-scale cryogenic experiment proposed as a follow-up to CUORE with particle identification