Measurement of the 2$νββ$ Decay Half-Life of Se-82 with the Global CUPID-0 Background Model
nucl-ex
/ Authors
O. Azzolini, J. W. Beeman, F. Bellini, M. Beretta, M. Biassoni, C. Brofferio, C. Bucci, S. Capelli, V. Caracciolo, L. Cardani
and 42 more authors
P. Carniti, N. Casali, E. Celi, D. Chiesa, M. Clemenza, I. Colantoni, O. Cremonesi, A. Cruciani, A. D'Addabbo, I. Dafinei, S. Di Domizio, V. Dompè, G. Fantini, F. Ferroni, L. Gironi, A. Giuliani, P. Gorla, C. Gotti, G. Keppel, J. Kotila, M. Martinez, S. S. Nagorny, M. Nastasi, S. Nisi
/ Abstract
We report on the results obtained with the global CUPID-0 background model, which combines the data collected in the two measurement campaigns for a total exposure of 8.82~kg$\times$yr of $^{82}$Se. We identify with improved precision the background sources within the 3 MeV energy region, where neutrinoless double $β$-decay of $^{82}$Se and $^{100}$Mo is expected, making more solid the foundations for the background budget of the next-generation CUPID experiment. Relying on the excellent data reconstruction, we measure the two-neutrino double $β$-decay half-life of $^{82}$Se with unprecedented accuracy: $T_{1/2}^{2ν} = [8.69 \pm 0.05 \textrm{(stat.)}~^{+0.09}_{-0.06} \textrm{(syst.)}] \times 10^{19}~\textrm{yr}$.