Improved Limit on Neutrinoless Double-Beta Decay in $^{130}$Te with CUORE

Author(s): Collaboration, CUORE; Adams, DQ; Alduino, C; Alfonso, K; III, FT Avignone; Azzolini, O; Bari, G; Bellini, F; Benato, G; Biassoni, M; Branca, A; Brofferio, C; Bucci, C; Caminata, A; Campani, A; Canonica, L; Cao, XG; Capelli, S; Cappelli, L; Cardani, L; Carniti, P; Casali, N; Chiesa, D; Chott, N; Clemenza, M; Copello, S; Cosmelli, C; Cremonesi, O; Creswick, RJ; D'Addabbo, A; D'Aguanno, D; Dafinei, I; Davis, CJ; Dell'Oro, S; Domizio, S Di; Dompe, V; Fang, DQ; Fantini, G; Faverzani, M; Ferri, E; Ferroni, F; Fiorini, E; Franceschi, MA; Freedman, SJ; Fujikawa, BK; Giachero, A; Gironi, L; Giuliani, A; Gorla, P; Gotti, C; Gutierrez, TD; Han, K; Heeger, KM; Huang, RG; Huang, HZ; Johnston, J; Keppel, G; Kolomensky, Yu G; Ligi, C; Ma, YG; Ma, L; Marini, L; Maruyama, RH; Mei, Y; Moggi, N; Morganti, S; Napolitano, T; Nastasi, M; Nikkel, J; Nones, C; Norman, EB; Novati, V; Nucciotti, A; Nutini, I; O'Donnell, T; Ouellet, JL; Pagliarone, CE; Pagnanini, L; Pallavicini, M; Pattavina, L; Pavan, M; Pessina, G; Pettinacci, V; Pira, C; Pirro, S | Abstract: We report new results from the search for neutrinoless double-beta decay in $^{130}$Te with the CUORE detector. This search benefits from a four-fold increase in exposure, lower trigger thresholds and analysis improvements relative to our previous results. We observe a background of $(1.38\pm0.07)\cdot10^{-2}$ counts$/($keV$\cdot$kg$\cdot$yr$)$ in the $0\nu\beta\beta$ decay region of interest and, with a total exposure of 372.5 kg$\cdot$yr, we attain a median exclusion sensitivity of $1.7\cdot10^{25}$ yr. We find no evidence for $0\nu\beta\beta$ decay and set a $90\%$ CI Bayesian lower limit of $3.2\cdot10^{25}$ yr on the $^{130}$Te half-life for this process. In the hypothesis that $0\nu\beta\beta$ decay is mediated by light Majorana neutrinos, this results in an upper limit on the effective Majorana mass of 75-350 meV, depending on the nuclear matrix elements used.