CUORE sensitivity to [Formula omitted] decay Alduino, C; Alfonso, K; Artusa, D. R ...
The European physical journal. C, Particles and fields,
08/2017, Letnik:
77, Številka:
8
Journal Article
Recenzirano
We report a study of the CUORE sensitivity to neutrinoless double beta ( Formula omitted) decay. We used a Bayesian analysis based on a toy Monte Carlo (MC) approach to extract the exclusion ...sensitivity to the Formula omitted decay half-life ( Formula omitted) at Formula omitted credibility interval (CI) - i.e. the interval containing the true value of Formula omitted with Formula omitted probability - and the Formula omitted discovery sensitivity. We consider various background levels and energy resolutions, and describe the influence of the data division in subsets with different background levels. If the background level and the energy resolution meet the expectation, CUORE will reach a Formula omitted CI exclusion sensitivity of Formula omitted year with 3 months, and Formula omitted year with 5 years of live time. Under the same conditions, the discovery sensitivity after 3 months and 5 years will be Formula omitted year and Formula omitted year, respectively.
The Cryogenic Underground Observatory for Rare Events (CUORE) at Laboratori Nazionali del Gran Sasso of INFN in Italy is an experiment searching for neutrinoless double beta (0νββ) decay. Its main ...goal is to investigate this decay in 130Te, but its ton-scale mass and low background make CUORE sensitive to other rare processes as well. Here, in this Letter, we present our first results on the search for 0νββ decay of 128Te, the Te isotope with the second highest natural isotopic abundance. We find no evidence for this decay, and using a Bayesian analysis we set a lower limit on the 128Te 0νββ decay half-life of T1/2 > 3.6 x 1024 yr (90% CI). This represents the most stringent limit on the half-life of this isotope, improving by over a factor of 30 the previous direct search results, and exceeding those from geochemical experiments for the first time.
The Cryogenic Underground Observatory for Rare Events (CUORE) is a large-scale cryogenic experiment searching for neutrinoless double-beta decay (0νββ) in 130Te. The CUORE detector is made of natural ...tellurium, providing the possibility of rare event searches on isotopes other than 130Te. In this work we describe a search for neutrinoless positron-emitting electron capture (β+ EC ) decay in 120Te with a total TeO2 exposure of 355.7 kg yr, corresponding to 0.2405 kg yr of 120Te. Albeit 0νββ with two final-state electrons represents the most promising channel, the emission of a positron and two 511-keV γ 's make 0νβ+ EC decay signature extremely clear. To fully exploit the potential offered by the detector modularity we include events with different topology and perform a simultaneous fit of five selected signal signatures. Using blinded data we extract a median exclusion sensitivity of 3.4 × 1022 yr at 90% credibility interval (C.I.). After unblinding we find no evidence of 0νβ+ EC signal and set a 90% C.I. Bayesian lower limit of 2.9 × 1022 yr on 120Te half-life. This result improves by an order of magnitude the existing limit from the combined analysis of CUORE-0 and Cuoricino.
We measured two-neutrino double beta decay of 130Te using an exposure of 300.7 kg yr accumulated with the CUORE detector. Using a Bayesian analysis to fit simulated spectra to experimental data, it ...was possible to disentangle all the major background sources and precisely measure the two-neutrino contribution. The half-life is in agreement with past measurements with a strongly reduced uncertainty: T2ν1/2=7.71+0.08−0.06 (stat)+0.12−0.15 ( syst ) × 1020 yr . This measurement is the most precise determination of the 130Te 2 ν β β decay half-life to date.
We measured two-neutrino double beta decay of $^{130}$Te using an exposure of 300.7 kg$\cdot$yr accumulated with the CUORE detector. Using a Bayesian analysis to fit simulated spectra to experimental ...data, it was possible to disentangle all the major background sources and precisely measure the two-neutrino contribution. The half-life is in agreement with past measurements with a strongly reduced uncertainty: $T^{2\nu}_{1/2} = 7.71^{+0.08}_{-0.06}\mathrm{(stat.)}^{+0.12}_{-0.15}\mathrm{(syst.)}\times10^{20}$ yr. This measurement is the most precise determination of the $^{130}$Te 2$\nu\beta\beta$ decay half-life to date.
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