8,442 research outputs found
New measurement of double-β decays of 100Mo to excited states of 100Ru with the CUPID-Mo experiment
No full textThe CUPID-Mo experiment, located at the Laboratoire Souterrain de Modane (France), was a demonstrator experiment for CUPID. It consisted of an array of 20Li2100MoO4 (LMO) calorimeters, each equipped with a Ge light detector for particle identification. In this work, we present the result of a search for two-neutrino and neutrinoless double-β decays of 100Mo to the first 0+ and 2+ excited states of 100Ru using the full CUPID-Mo exposure (2.71kgyr of LMO). We measure the half-life of 2νββ decay to the 0+1 state as T2ν→0+11/2=(7.5±0.8(stat.)+0.4−0.3(syst.))×1020yr. The bolometric technique enables measurement of the electron energies as well as the γ rays from nuclear deexcitation and this allows us to set new limits on the two-neutrino decay to the 2+1 state of T2ν→2+11/2>4.4×1021yr(90% c.i.) and on the neutrinoless modes of T0ν→2+11/2>2.1×1023yr(90% c.i.), T0ν→0+11/2>1.2×1023yr(90% c.i.). Information on the electrons' spectral shape is obtained, which allows us to make the first comparison of the single and higher state dominance 2νββ decay models for the 0+1 excited state of 100Ru.peerReviewe
Measurement of the 2νββ Decay Rate and Spectral Shape of 100Mo from the CUPID-Mo Experiment
No full textNeutrinoless double beta decay (0νββ) is a yet unobserved nuclear process that would demonstrate Lepton number violation, a clear evidence of beyond standard model physics. The process two neutrino double beta decay (2νββ) is allowed by the standard model and has been measured in numerous experiments. In this Letter, we report a measurement of 2νββ decay half-life of 100Mo to the ground state of 100Ru of [7.07±0.02(stat)±0.11(syst)]×1018 yr by the CUPID-Mo experiment. With a relative precision of ±1.6% this is the most precise measurement to date of a 2νββ decay rate in 100Mo. In addition, we constrain higher-order corrections to the spectral shape, which provides complementary nuclear structure information. We report a novel measurement of the shape factor ξ3,1=0.45±0.03(stat)±0.05(syst) based on a constraint on the ratio of higher-order terms from theory, which can be reliably calculated. This is compared to theoretical predictions for different nuclear models. We also extract the first value for the effective axial vector coupling constant obtained from a spectral shape study of 2νββ decay.peerReviewe
CUPID, the Cuore upgrade with particle identification
No full textAbstract CUPID, the CUORE Upgrade with Particle Identification, is a next-generation experiment to search for neutrinoless double beta decay ( 0 ν β β ) and other rare events using enriched Li 2 100 MoO 4 scintillating bolometers. It will be hosted by the CUORE cryostat located at the Laboratori Nazionali del Gran Sasso in Italy. The main physics goal of CUPID is to search for 0 ν β β of 100 Mo with a discovery sensitivity covering the full neutrino mass regime in the inverted ordering scenario, as well as the portion of the normal ordering regime with lightest neutrino mass larger than 10 meV. With a conservative background index of 10 - 4 cts / ( keV · kg · yr ) , 240 kg isotope mass, 5 keV FWHM energy resolution at 3 MeV and 10 live-years of data taking, CUPID will have a 90% C.L. half-life exclusion sensitivity of 1.8 · 10 27 yr, corresponding to an effective Majorana neutrino mass ( m β β ) sensitivity of 9–15 meV, and a 3 σ discovery sensitivity of 1 · 10 27 yr, corresponding to an m β β range of 12–21 meV
Status of cupid-mo
No full textCUPID-Mo is a bolometric experimental demonstrator searching for neutrinoless double beta (0ν2β) decay of 100Mo. The observation of this process, which is not allowed by the Standard Model, would determine the Majorana nature of neutrino and its mass scale. The CUPID-Mo detector array consists of 20 scintillating bolometers made of Li2100MoO4 crystals (2.34 kg of 100Mo), assembled in a compact structure of 5 suspended towers. Data taking will start soon in the EDELWEISS cryostat at the Underground Laboratory of Modane (LSM, France). The main goal of the CUPID-Mo experiment is to demonstrate “zero-background” conditions in the region of the expected 0ν2β decay signal of 100Mo over six months of measurement. The reproducibility of Li2100MoO4 scintillating bolometers with high performance should be confirmed, demonstrating the applicability of the CUPID-Mo technology for the future ton-scale 0ν2β decay bolometric experiment CUPID
ESDIAPOK poster
No full textPoster presentation of DEN CuPID at the conference of the Society of Cultural Heritage Management Consultants The Society of Cultural Heritage Management Consultants (ΕΣΔΙΑΠΟΚ) is a relatively new not-for-profit organization whose members all have a degree in heritage management. Its aim is to contribute to the preservation of cultural heritage and to promote its sustainable development. On March 31st and April 1st ΕΣΔΙΑΠΟΚ organized its 3rd annual conference in the Cultural Center of the Municipality of Athens. The theme of he Conference was “Cultural Heritage and Universal Challenges”. DEN CuPID was presented in the form of a poster and flyers about the project were inserted in all giveaway folders to participants. There was vivid interest in the project and many people asked to be informed about it. The poster was prepared in collaboration by Time Heritage and the University of Patras
Mo-100 double-beta decay search in the CUPID-Mo experiment with enriched scintillating bolometers
No full textKnow-how of 100Mo-enriched Li2MoO4 scintillating bolometers has been recently developed by the LUMINEU Collaboration as a part of the R&D activities towards a tonne-scale 0ν2β experiment CUPID. The reproducibility of high performance (~5-6 keV FWHM at 2615 keV, α background rejection on the level of about 9σ) and radiopurity (below 10 μBq/kg U/Th activity) has been demonstrated in multiple tests. Moreover, with only ~0.1 kg*yr of 100Mo exposure, the measured 2ν2β decay half-life is one of the most precise values ever reported. As a follow-up of this activity, a demonstrator named CUPID-Mo is now ready to collect data in the Modane underground laboratory. CUPID-Mo consists of twenty 0.2-kg 100Mo-enriched Li2MoO4 scintillating bolometers (containing more than 2 kg of 100Mo) to be operated for at least 0.5 yr providing a sensitivity to 0ν2β decay of 100Mo larger than 1024
^{24}
yr. A prolongation of the experiment and its extension to the available ~7 kg of 100Mo are under consideration
A gravity-based mounting approach for large-scale cryogenic calorimeter arrays
No full textCryogenic calorimeters are among the leading technologies for searching for rare events. The CUPID experiment is exploiting this technology to deploy a tonne-scale detector to search for neutrinoless double-beta decay of 100 Mo. The CUPID collaboration proposed an innovative approach to assembling cryogenic calorimeters in a stacked configuration, held in position solely by gravity. This gravity-based assembly method is unprecedented in the field of cryogenic calorimeters and offers several advantages, including relaxed mechanical tolerances and simplified construction. To assess and optimize its performance, we constructed a medium-scale prototype hosting 28 Li 2 MoO 4 crystals and 30 Ge light detectors, both operated as cryogenic calorimeters at the Laboratori Nazionali del Gran Sasso (Italy). Despite an unexpected excess of noise in the light detectors, the results of this test proved (i) a thermal stability better than ±0.5 mK at 10 mK, (ii) a good energy resolution of Li 2 MoO 4 cryogenic calorimeters, (6.6 ± 2.2) keV FWHM at 2615 keV, and (iii) a Li 2 MoO 4 light yield measured by the closest light detector of 0.36 keV/MeV, sufficient to guarantee the particle identification requested by CUPID
Search for Majoron-like particles with CUPID-0
No full textWe present the first search for the Majoron-emitting modes of the neutrinoless double β decay (0νββχ0) using scintillating cryogenic calorimeters. We analyzed the CUPID-0 Phase I data using a Bayesian approach to reconstruct the background sources activities, and evaluate the potential contribution of the 82Se 0νββχ0. We considered several possible theoretical models which predict the existence of a Majoron-like boson coupling to the neutrino. The energy spectra arising from the emission of such bosons in the neutrinoless double β decay have spectral indices n=1, 2, 3, or 7. We found no evidence of any of these decay modes, setting a lower limit (90% of credibility interval) on the half-life of 1.2×1023 yr in the case of n=1, 3.8×1022 yr for n=2, 1.4×1022 yr for n=3 and 2.2×1021 yr for n=7. These are the best limits on the 0νββχ0 half-life of the 82Se, and demonstrate the potentiality of the CUPID-0 technology in this field.peerReviewe
The European Physical Journal C
No full textCryogenic calorimeters are among the leading technologies for searching for rare events. The CUPID experiment is exploiting this technology to deploy a tonne-scale detector to search for neutrinoless double-beta decay of 100 Mo. The CUPID collaboration proposed an innovative approach to assembling cryogenic calorimeters in a stacked configuration, held in position solely by gravity. This gravity-based assembly method is unprecedented in the field of cryogenic calorimeters and offers several advantages, including relaxed mechanical tolerances and simplified construction. To assess and optimize its performance, we constructed a medium-scale prototype hosting 28 Li 2 MoO 4 crystals and 30 Ge light detectors, both operated as cryogenic calorimeters at the Laboratori Nazionali del Gran Sasso (Italy). Despite an unexpected excess of noise in the light detectors, the results of this test proved (i) a thermal stability better than ±0.5 mK at 10 mK, (ii) a good energy resolution of Li 2 MoO 4 cryogenic calorimeters, (6.6 ± 2.2) keV FWHM at 2615 keV, and (iii) a Li 2 MoO 4 light yield measured by the closest light detector of 0.36 keV/MeV, sufficient to guarantee the particle identification requested by CUPID.Published versio
The background model of the CUPID-Mo experiment
No full textCUPID-Mo, located in the Laboratoire Souterrain de Modane (France), was a
demonstrator for the next generation decay experiment, CUPID.
It consisted of an array of 20 enriched LiMoO bolometers and
20 Ge light detectors and has demonstrated that the technology of scintillating
bolometers with particle identification capabilities is mature. Furthermore,
CUPID-Mo can inform and validate the background prediction for CUPID. In this
paper, we present a detailed model of the CUPID-Mo backgrounds. This model is
able to describe well the features of the experimental data and enables studies
of the decay and other processes with high precision. We also
measure the radio-purity of the LiMoO crystals which are
found to be sufficient for the CUPID goals. Finally, we also obtain a
background index in the region of interest of
3.7(stat)(syst)counts/E/mol/yr,
the lowest in a bolometric decay experiment
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