First Result on the Neutrinoless Double Beta Decay of $^{82}$Se with CUPID-0
nucl-ex
/ Authors
CUPID-0 collaboration, :, O. Azzolini, M. T. Barrera, J. W. Beeman, F. Bellini, M. Beretta, M. Biassoni, C. Brofferio, C. Bucci
and 43 more authors
L. Canonica, S. Capelli, L. Cardani, P. Carniti, N. Casali, L. Cassina, M. Clemenza, O. Cremonesi, A. Cruciani, A. D'Addabbo, I. Dafinei, S. Di Domizio, F. Ferroni, L. Gironi, A. Giuliani, P. Gorla, C. Gotti, G. Keppel, L. Marini, M. Martinez, S. Morganti, S. Nagorny, M. Nastasi, S. Nisi
/ Abstract
We report the result of the search for neutrinoless double beta decay of $^{82}$Se obtained with CUPID-0, the first large array of scintillating Zn$^{82}$Se cryogenic calorimeters implementing particle identification. We observe no signal in a 1.83 kg yr $^{82}$Se exposure and we set the most stringent lower limit on the \onu $^{82}$Se half-life T$^{0ν}_{1/2}>$ 2.4$\times \mathrm{10}^{24}$ yr (90\% credible interval), which corresponds to an effective Majorana neutrino mass m$_{ββ} <$ (376-770) meV depending on the nuclear matrix element calculations. The heat-light readout provides a powerful tool for the rejection of \al\ particles and allows to suppress the background in the region of interest down to (3.6$^{+1.9}_{-1.4}$)$\times$10$^{-3}$\ckky, an unprecedented level for this technique.