Search for Neutrinoless Double-Beta Decay of Te 130 with CUORE-0

We report the results of a search for neutrinoless double-beta decay in a 9.8 kg yr exposure of Te130 using a bolometric detector array, CUORE-0. The characteristic detector energy resolution and background level in the region of interest are 5.1±0.3keV FWHM and 0.058±0.004(stat)±0.002(syst)counts/(keVkgyr), respectively. The median 90% C.L. lower-limit half-life sensitivity of the experiment is 2.9×1024yr and surpasses the sensitivity of previous searches. We find no evidence for neutrinoless double-beta decay of Te130 and place a Bayesian lower bound on the decay half-life, T1/20ν>2.7×1024yr at 90% C.L. Combining CUORE-0 data with the 19.75 kg yr exposure of Te130 from the Cuoricino experiment we obtain T1/20ν>4.0×1024yr at 90% C.L. (Bayesian), the most stringent limit to date on this half-life. Using a range of nuclear matrix element estimates we interpret this as a limit on the effective Majorana neutrino mass, mββ<270-760meV.