After a one-year stay in the Modane underground laboratory, the CUPID-Mo demonstrator, equipped with its brand new scintillating Li2MoO4 bolometers, has obtained very promising results. With a monitored mass equivalent to 1.2 kg of Mo year, the detector is already able to surpass its predecessor NEMO in precision, which nevertheless established its measurements with 34.4 kg per year. The worldwide limit for the measurement of the half-life of the double beta decay without neutrino emission (0νββ) thus drops from 1.1 × 1024 to 1.4 × 1024 years, ie a gain of about 30%. Better yet, the background noise at 3034 keV, the energy at which the 0νββ event is to be perceived, is not masked by any background noise. The background level thus exceeds the value of the large-scale CUORE bolometric experiment currently taking data at the Gran Sasso underground laboratory. Finally, the scintillating bolometer technology, one of the major innovations of the demonstrator, is a determining factor in the elimination of alpha and gamma noise.
Now the crystals will continue their stay in Modane for final calibration in the region of interest. CUPID-Mo's scintillating bolometers have been selected to equip the proposed CUPID large-scale future experiment, which could be assembled in CUORE's cryogenic infrastructure after 2023.