Engineering topics

Domizio, S. Di

Publications and source records attributed to Domizio, S. Di.

9 records

DOE OSTI2022

CUPID: The Next-Generation Neutrinoless Double Beta Decay Experiment

We report CUPID is a next-generation tonne-scale bolometric neutrinoless double beta decay experiment that will probe the Majorana nature of neutrinos and discover lepton number violation in case of observation of this singular process. CUPID will be built on experience, expertise and lessons learned in CUORE and will be installed in the current CUORE infra-structure in the Gran Sasso underground laboratory. The CUPID detector technology, successfully tested in the CUPID-Mo experiment, is based on scintillating bolometers of Li 2 MoO 4 enriched in the isotope of interest 100 Mo. In order to achieve its ambitious science goals, the CUPID collaboration aims to reduce the backgrounds in the region of interest by a factor 100 with respect to CUORE. This performance will be achieved by introducing the high efficient α/β discrimination demonstrated by the CUPID-0 and CUPID-Mo experiments, and using a high transition energy double beta decay nucleus such as 100 Mo to minimize the impact of the gamma background. CUPID will consist of about 1500 hybrid heat-light detectors for a total isotope mass of 250 kg. The CUPID scientific reach is supported by a detailed and safe background model based on CUORE, CUPID-Mo and CUPID-0 results. The required performances have already been demonstrated and will be presented.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2022

Latest Results from the CUORE Experiment

Abstract The Cryogenic Underground Observatory for Rare Events (CUORE) is the first cryogenic experiment searching for $$0\nu \beta \beta $$ 0 ν β β decay that has been able to reach the one-tonne mass scale. The detector, located at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy, consists of an array of 988 $${\mathrm{TeO}}_{2}$$ TeO 2 crystals arranged in a compact cylindrical structure of 19 towers. CUORE began its first physics data run in 2017 at a base temperature of about 10 mK and in April 2021 released its $$3{\mathrm{rd}}$$ 3 rd result of the search for $$0\nu \beta \beta $$ 0 ν β β , corresponding to a tonne-year of $$\mathrm{TeO}_{2}$$ TeO 2 exposure. This is the largest amount of data ever acquired with a solid state detector and the most sensitive measurement of $$0\nu \beta \beta $$ 0 ν β β decay in $${}^{130}\mathrm{Te}$$ 130 Te ever conducted . We present the current status of CUORE search for $$0\nu \beta \beta $$ 0 ν β β with the updated statistics of one tonne-yr. We finally give an update of the CUORE background model and the measurement of the $${}^{130}\mathrm{Te}$$ 130 Te $$2\nu \beta \beta $$ 2 ν β β decay half-life and decay to excited states of $${}^{130}\mathrm{Xe}$$ 130 Xe , studies performed using an exposure of 300.7 kg yr.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2022

Machine Learning Techniques for Pile-Up Rejection in Cryogenic Calorimeters

CUORE Upgrade with Particle IDentification (CUPID) is a foreseen ton-scale array of Li 2 MoO 4 (LMO) cryogenic calorimeters with double readout of heat and light signals. Its scientific goal is to fully explore the inverted hierarchy of neutrino masses in the search for neutrinoless double beta decay of 100 Mo. Pile-up of standard double beta decay of the candidate isotope is a relevant background. We generate pile-up heat events via injection of Joule heater pulses with a programmable waveform generator in a small array of LMO crystals operated underground in the Laboratori Nazionali del Gran Sasso, Italy. This allows to label pile-up pulses and control both time difference and underlying amplitudes of individual heat pulses in the data. We present the performance of supervised learning classifiers on data and the attained pile-up rejection efficiency.

47 OTHER INSTRUMENTATION↗

DOE OSTI2021

Optimization of a single module of CUPID

CUPID is the next generation experiment which will use scintillating cryogenic calorimeters to search for the neutrinoless double β decay. This unobserved process would shed light on the nature of the neutrino, which up to our knowledge could be a Majorana or a Dirac particle, and would give us an important hint to explain the lack of antimatter in the universe. This ambitious search needs a detector with unique characteristics such as an extremely low background level and an excellent energy resolution. CUPID is now in advanced R&D state to optimize the detector design in order to completely exploit the potentialities of scintillating cryogenic calorimeters. In the following I will describe the test performed at the LNGS (Laboratori Nazionali del Gran Sasso) of a single module of the future CUPID detector. In this contribution we present the performance obtained with a novel assembly concept, proving that it matches the requirements for CUPID.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2021

Searching for New Physics in two-neutrino double beta decay with CUPID

In the past few years, attention has been drawn to the fact that a precision analysis of two-neutrino double beta decay (2υββ) allows the study of interesting physics cases like the emission of Majoron bosons and possible Lorentz symmetry violation. These processes modify the summed-energy distribution of the two electrons emitted in 2υββ. CUPID is a next-generation experiment aiming to exploit 100 Mo-enriched scintillating Li 2 MoO 4 crystals, operating as cryogenic calorimeters. Given the relatively fast half-life of 100 Mo 2υββ and the large exposure that can be reached by CUPID, we expect to measure with very high precision the 100 Mo 2υββ spectrum shape, reaching great sensitivities in the search for distortions induced by the physics beyond the Standard Model. In this contribution, we present the CUPID exclusion sensitivity for such New Physics processes, as well as the preliminary projected background of CUPID.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2021

Search for double-beta decay of $$\mathrm {^{130}Te}$$ to the $$0^+$$ states of $$\mathrm {^{130}Xe}$$ with CUORE

Abstract The CUORE experiment is a large bolometric array searching for the lepton number violating neutrino-less double beta decay ( $$0\nu \beta \beta $$ 0 ν β β ) in the isotope $$\mathrm {^{130}Te}$$ 130 Te . In this work we present the latest results on two searches for the double beta decay (DBD) of $$\mathrm {^{130}Te}$$ 130 Te to the first $$0^{+}_2$$ 0 2 + excited state of $$\mathrm {^{130}Xe}$$ 130 Xe : the $$0\nu \beta \beta $$ 0 ν β β decay and the Standard Model-allowed two-neutrinos double beta decay ( $$2\nu \beta \beta $$ 2 ν β β ). Both searches are based on a 372.5 kg $$\times $$ × yr TeO $$_2$$ 2 exposure. The de-excitation gamma rays emitted by the excited Xe nucleus in the final state yield a unique signature, which can be searched for with low background by studying coincident events in two or more bolometers. The closely packed arrangement of the CUORE crystals constitutes a significant advantage in this regard. The median limit setting sensitivities at 90% Credible Interval (C.I.) of the given searches were estimated as $$\mathrm {S^{0\nu }_{1/2} = 5.6 \times 10^{24} \, \mathrm {yr}}$$ S 1 / 2 0 ν = 5.6 × 10 24 yr for the $${0\nu \beta \beta }$$ 0 ν β β decay and $$\mathrm {S^{2\nu }_{1/2} = 2.1 \times 10^{24} \, \mathrm {yr}}$$ S 1 / 2 2 ν = 2.1 × 10 24 yr for the $${2\nu \beta \beta }$$ 2 ν β β decay. No significant evidence for either of the decay modes was observed and a Bayesian lower bound at $$90\%$$ 90 % C.I. on the decay half lives is obtained as: $$\mathrm {(T_{1/2})^{0\nu }_{0^+_2} > 5.9 \times 10^{24} \, \mathrm {yr}}$$ ( T 1 / 2 ) 0 2 + 0 ν > 5.9 × 10 24 yr for the $$0\nu \beta \beta $$ 0 ν β β mode and $$\mathrm {(T_{1/2})^{2\nu }_{0^+_2} > 1.3 \times 10^{24} \, \mathrm {yr}}$$ ( T 1 / 2 ) 0 2 + 2 ν > 1.3 × 10 24 yr for the $$2\nu \beta \beta $$ 2 ν β β mode. These represent the most stringent limits on the DBD of $$^{130}$$ 130 Te to excited states and improve by a factor $$\sim 5$$ ∼ 5 the previous results on this process.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2021

A CUPID Li2100MoO4 scintillating bolometer tested in the CROSS underground facility

A scintillating bolometer based on a large cubic Li$_{2}$$^{100}$MoO$_4$ crystal (45 mm side) and a Ge wafer (scintillation detector) has been operated in the CROSS cryogenic facility at the Canfranc underground laboratory in Spain. The dual-readout detector is a prototype of the technology that will be used in the next-generation $0\nu2\beta$ experiment CUPID. The measurements were performed at 18 and 12 mK temperature in a pulse tube dilution refrigerator. This setup utilizes the same technology as the CUORE cryostat that will host CUPID and so represents an accurate estimation of the expected performance. The Li$_{2}$$^{100}$MoO$_4$ bolometer shows a high energy resolution of 6 keV FWHM at the 2615 keV $\gamma$ line. The detection of scintillation light for each event triggered by the Li$_{2}$$^{100}$MoO$_4$ bolometer allowed for a full separation ($\sim$8$\sigma$) between $\gamma$($\beta$) and $\alpha$ events above 2 MeV. The Li$_{2}$$^{100}$MoO$_4$ crystal also shows a high internal radiopurity with $^{228}$Th and $^{226}$Ra activities of less than 3 and 8 $\mu$Bq/kg, respectively. Taking also into account the advantage of a more compact and massive detector array, which can be made of cubic-shaped crystals (compared to the cylindrical ones), this test demonstrates the great potential of cubic Li$_{2}$$^{100}$MoO$_4$ scintillating bolometers for high-sensitivity searches for the $^{100}$Mo $0\nu2\beta$ decay in CROSS and CUPID projects.

47 OTHER INSTRUMENTATION↗

DOE OSTI2020

Perspectives of lowering CUORE thresholds with Optimum Trigger

CUORE is a cryogenic experiment that focuses on the search of neutrinoless double beta decay in 130Te and it is located at the Gran Sasso National Laboratories. Its detector consists of 988 TeO 2 crystals operating at a base temperature of ~10 mK. It is the first ton-scale bolometric experiment ever realized for this purpose. Thanks to its large target mass and ultra-low background, the CUORE detector is also suitable for the search of other rare phenomena. In particular the low energy part of the spectra is interesting for the detection of WIMP-nuclei scattering reactions. One of the most important requirements to perform these studies is represented by the achievement of a stable energy threshold lower than 10 keV. Here, the CUORE capability to accomplish this purpose using a low energy software trigger will be presented and described.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2020

The CUORE Detector and Results

The cryogenic underground observatory for rare events (CUORE) is a cryogenic experiment searching for neutrinoless double beta decay (0νββ) of 130 Te. The detector consists of an array of 988TeO 2 crystals arranged in a compact cylindrical structure of 19 towers. We report the CUORE initial operations and optimization campaigns. We then present the CUORE results on 0νββ and 2νββ decay of 130 Te obtained from the analysis of the physics data acquired in 2017.

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