The CUORE experiment, a ton-scale cryogenic bolometer array, recently began operation at the Laboratori Nazionali del Gran Sasso in Italy. The array represents a significant advancement in this technology, and in this work we apply it for the first time to a high-sensitivity search for a lepton-numberviolating process: 130Te neutrinoless double-beta decay. Examining a total TeO2 exposure of 86.3 kg/yr, characterized by an effective energy resolution of (7.7 +/- 0.5) keV FWHM and a background in the region of interest of (0.014 +/- 0.002) counts/keV kg yr, we find no evidence for neutrinoless double-beta decay. Including systematic uncertainties, we place a lower limit on the decay half-life of T0ν 1/2 (130Te) >1.3 × 10^25 yr (90% C.L.); the median statistical sensitivity of this search is 7.0 × 10^24 yr. Combining this result with those of two earlier experiments, Cuoricino and CUORE-0, we find T0ν1/2(130Te) > 1.5 × 10^25 yr (90% C.L.), which is the most stringent limit to date on this decay. Interpreting this result as a limit on the effective Majorana neutrino mass, we find mββ < (110 − 520) meV, where the range reflects the nuclear matrix element estimates employed.
First Results from CUORE: A Search for Lepton Number Violation via 0νββ Decay of 130Te
C. E. Pagliarone;
2018-01-01
Abstract
The CUORE experiment, a ton-scale cryogenic bolometer array, recently began operation at the Laboratori Nazionali del Gran Sasso in Italy. The array represents a significant advancement in this technology, and in this work we apply it for the first time to a high-sensitivity search for a lepton-numberviolating process: 130Te neutrinoless double-beta decay. Examining a total TeO2 exposure of 86.3 kg/yr, characterized by an effective energy resolution of (7.7 +/- 0.5) keV FWHM and a background in the region of interest of (0.014 +/- 0.002) counts/keV kg yr, we find no evidence for neutrinoless double-beta decay. Including systematic uncertainties, we place a lower limit on the decay half-life of T0ν 1/2 (130Te) >1.3 × 10^25 yr (90% C.L.); the median statistical sensitivity of this search is 7.0 × 10^24 yr. Combining this result with those of two earlier experiments, Cuoricino and CUORE-0, we find T0ν1/2(130Te) > 1.5 × 10^25 yr (90% C.L.), which is the most stringent limit to date on this decay. Interpreting this result as a limit on the effective Majorana neutrino mass, we find mββ < (110 − 520) meV, where the range reflects the nuclear matrix element estimates employed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
