Final results of the CUPID-0 Phase I experiment Casali, N; Azzolini, O; Beeman, J W ...
Journal of physics. Conference series,
02/2020, Letnik:
1468, Številka:
1
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
A convincing observation of neutrino-less double beta decay (0vDBD) relies on the possibility of operating high-energy resolution detectors in background-free conditions. Scintillating cryogenic ...calorimeters are one of the most promising tools to fulfill the requirements for a next-generation experiment. Several steps have been taken to demonstrate the maturity of this technique, starting form the successful experience of CUPID-0. The CUPID-0 experiment collected almost 10 kg y of exposure, running 26 Zn82Se crystals during two years of continuous detector operation. The complete rejection of the dominant α background was demonstrated, measuring the lowest counting rate in the region of interest for this technique. Furthermore, the most stringent limit on the 82Se 0vDBD was established. In this contribution we present the final results of CUPID-0 phase-I, including a detailed model of the background and the measurement of the 2vDBD half-life.
► We measured the elongation of a loaded Kevlar-49 fiber at 4.2K. ► We kept a fiber under a constant tension for 8months. ► We obtained an upper limit of 0.028% in the relative elongation. ► The ...results shows that Kevlar-49 can be used in cryogenic applications.
We have measured the rate of elongation of a loaded Kevlar-49 fiber as a function of time at 4.2K. The result puts a worst case upper limit of 0.028% in the elongation rate ΔL/L for a 0.5mm diameter fiber kept under a constant tension of 2.7kg for 8months. A value that is probably closer to reality is actually 0.004%. This result proves that Kevlar-49 can be safely used in cryogenic applications in which high mechanical stability under stress is required.
The CUPID-0 experiment searches for double beta decay using cryogenic calorimeters with double (heat and light) read-out. The detector, consisting of 24 ZnSe crystals 95 Formula omitted enriched in ...Formula omittedSe and two natural ZnSe crystals, started data-taking in 2017 at Laboratori Nazionali del Gran Sasso. We present the search for the neutrino-less double beta decay of Formula omittedSe into the 0 Formula omitted, 2 Formula omitted and 2 Formula omitted excited states of Formula omittedKr with an exposure of 5.74 kg Formula omittedyr (2.24 Formula omitted10 Formula omitted emitters Formula omittedyr). We found no evidence of the decays and set the most stringent limits on the widths of these processes: Formula omitted( Formula omittedSe Formula omittedKr Formula omitted)8.55 Formula omitted10 Formula omitted yr Formula omitted, Formula omitted ( Formula omitted Se Formula omitted Kr Formula omitted) Formula omitted yr Formula omitted, Formula omitted( Formula omittedSe Formula omittedKr Formula omitted)8.25 Formula omitted10 Formula omitted yr Formula omitted (90 Formula omitted credible interval).
CUPID is a proposed future tonne-scale bolometric neutrino-less double beta decay (0νββ) experiment to probe the Majorana nature of neutrinos and discover lepton number violation in the so-called ...inverted hierarchy region of the neutrino mass. In order to improve the sensitivity with respect to the current bolometric experiments, the source mass must be increased and the backgrounds in the region of interest must be dramatically reduced. The background suppression can be achieved discriminating β/γ against α events by means of the different light yield produced in the interactions within a scintillating bolometer. The increase in the number of 0νββ emitters demands for crystals grown with enriched material. LUCIFER/CUPID-0, the first demonstrator of CUPID, aims at running the first array of enriched scintillating Zn82Se bolometers (total mass of about 7kg of 82Se) with a background level as low as 10−3 counts/(keVkgy) in the energy region of interest. We present the results of the first measurement performed on three Zn82Se enriched scintillating bolometers operated deep underground in the Hall C of the Laboratori Nazionali del Gran Sasso.
The goal of the Cryogenic wide-Area Light Detectors with Excellent Resolution project is the development of light detectors with large active area and noise energy resolution smaller than 20 eV RMS ...using phonon-mediated kinetic inductance detectors. The detectors are developed to improve the background suppression in large-mass bolometric experiments such as CUORE, via the double read-out of the light and the heat released by particles interacting in the bolometers. In this work, we present the design and the fabrication process, starting from the silicon wafer arriving to the single chip. The Al thin films (40 nm) are evaporated on high-quality, high-resistivity (>
10
k
Ω
cm) Si(100) substrates using an electron beam evaporator in a high-vacuum chamber. Detectors are patterned in direct-write mode, using electron beam lithography , positive tone resist poly-methyl methacrylate and lift-off process. Finally the wafer is diced into 20
×
20 mm
2
chips and assembled in a holder OFHC copper (oxygen-free high conductivity) using PTFE supports.
The main goal of the AEgIS experiment at CERN is to test the weak equivalence principle for antimatter. We will measure the Earth's gravitational acceleration g¯ with antihydrogen atoms being ...launched in a horizontal vacuum tube and traversing a moiré deflectometer. We intend to use a position sensitive device made of nuclear emulsions (combined with a time-of-flight detector such as silicon μ-strips) to measure precisely their annihilation points at the end of the tube. The goal is to determine g¯ with a 1% relative accuracy. In 2012 we tested emulsion films in vacuum and at room temperature with low energy antiprotons from the CERN antiproton decelerator. First results on the expected performance for AEgIS are presented.
First results and perspectives of CALDER Vignati, M.; Bellini, F.; Cardani, L. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
07/2016, Letnik:
824
Journal Article
Recenzirano
Large-mass arrays of bolometers proved to be good detectors for Neutrinoless Double Beta Decay (0νββ) and Dark Matter searches. CUORE and LUCIFER are bolometric 0νββ experiments which will start to ...take data in 2016 at Laboratori Nazionali del Gran Sasso in Italy. The sensitivity of CUORE could be increased by removing the background due to α particles, by detecting the small amount of Cherenkov light (100eV) emitted by the βs׳ signal and not by αs. LUCIFER could be extended to detect also Dark Matter, provided that the background from β/γ particles (100eV of scintillation light) is discriminated from nuclear recoils of about 10keV energy (no light). CALDER is a project to develop light detectors for CUORE, LUCIFER and similar bolometric experiments. The goal is to obtain detectors with an active area of 5×5cm2 (the face of bolometric crystals), operating at 10mK, and with a baseline resolution better than 20eV. We have chosen to develop phonon-mediated devices using Kinetic Inductance Detectors (KIDs). We present the first results and the perspectives of the project.
0νββ decay: the CUPID-0 experiment Azzolini, O; Barrera, M T; Beeman, J W ...
Journal of physics. Conference series,
07/2018, Letnik:
1056, Številka:
1
Journal Article
Recenzirano
Odprti dostop
CUPID-0 is an array of 24 Zn82Se scintillating bolometers used to search for the 0νββ decay of 82Se. It is the first large mass 0νββ experiment exploiting a double read-out technique: the phonon ...signal to accurately measure particle energies and the light signal to reject the α-induced background. Its success might open the road to a next generation project of ton mass scale, CUPID. The array is in operation at Laboratori Nazionali del Gran Sasso since the beginning of 2017, in this paper we present the preliminary results obtained with an exposure of 10.45 kg· y.
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