First result on the neutrinoless double-β decay of 82Se with CUPID-0

We report the result of the search for neutrinoless double beta decay of 82Se obtained with CUPID-0, the first large array of scintillating Zn82Se cryogenic calorimeters implementing particle identification. We observe no signal in a 1.83 kg yr 82Se exposure, and we set the most stringent lower limit on the 0vββ 82Se half-life T0v 1=2 > 2.4 × 1024 yr (90% credible interval), which corresponds to an effective Majorana neutrino mass mββ < (376-770) meV depending on the nuclear matrix element calculations. The heat-light readout provides a powerful tool for the rejection of α particles and allows us to suppress the background in the region of interest down to (3.6 +1.9-1.4) × 10-3counts=(keV kg yr), an unprecedented level for this technique.