This article presents an analysis and the resulting limits on light dark matter inelastically scattering off of electrons, and on dark photon and axionlike particle absorption, using a ...second-generation SuperCDMS high-voltage eV-resolution detector. The 0.93 g Si detector achieved a 3 eV phonon energy resolution; for a detector bias of 100 V, this corresponds to a charge resolution of 3% of a single electron-hole pair. The energy spectrum is reported from a blind analysis with 1.2 g-days of exposure acquired in an above-ground laboratory. With charge carrier trapping and impact ionization effects incorporated into the dark matter signal models, the dark matter-electron cross section σe is constrained for dark matter masses from 0.5 to 104 MeV / c2; in the mass range from 1.2 to 50 eV / c2 the dark photon kinetic mixing parameter ϵ and the axioelectric coupling constant gae are constrained. The minimum 90% confidence-level upper limits within the above-mentioned mass ranges are σe = 8.7 × 10−34 cm2, ϵ = 3.3 × 10−14, and gae = 1.0 × 10−9.
The projected background for the CUORE experiment Alduino, C.; Avignone, F. T.; Azzolini, O. ...
The European physical journal. C, Particles and fields,
08/2017, Letnik:
77, Številka:
8
Journal Article
Recenzirano
Odprti dostop
The Cryogenic Underground Observatory for Rare Events (CUORE) is designed to search for neutrinoless double beta decay of
130
Te with an array of 988 TeO
2
bolometers operating at temperatures ...around 10 mK. The experiment is currently being commissioned in Hall A of Laboratori Nazionali del Gran Sasso, Italy. The goal of CUORE is to reach a 90% C.L. exclusion sensitivity on the
130
Te decay half-life of 9
×
10
25
years after 5 years of data taking. The main issue to be addressed to accomplish this aim is the rate of background events in the region of interest, which must not be higher than 10
-
2
counts/keV/kg/year. We developed a detailed Monte Carlo simulation, based on results from a campaign of material screening, radioassays, and bolometric measurements, to evaluate the expected background. This was used over the years to guide the construction strategies of the experiment and we use it here to project a background model for CUORE. In this paper we report the results of our study and our expectations for the background rate in the energy region where the peak signature of neutrinoless double beta decay of
130
Te is expected.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•A large custom cryogen-free cryostat has been designed and built in order to operate the CUORE detector.•The CUORE cryostat has a 1 m3 experimental volume and is able to host a tonne-scale ...bolometric detector.•The CUORE cryostat guarantees a low noise and low radioactivity environment, needed to search for 0nbb.•The CUORE detector has been cooled down to 8.3 mK and steadily operated at 15 mK, proving the success of the cryostat.
The CUORE experiment is the world’s largest bolometric experiment. The detector consists of an array of 988 TeO2 crystals, for a total mass of 742 kg. CUORE is presently taking data at the Laboratori Nazionali del Gran Sasso, Italy, searching for the neutrinoless double beta decay of 130Te. A large custom cryogen-free cryostat allows reaching and maintaining a base temperature of ∼10 mK, required for the optimal operation of the detector. This apparatus has been designed in order to achieve a low noise environment, with minimal contribution to the radioactive background for the experiment. In this paper, we present an overview of the CUORE cryostat, together with a description of all its sub-systems, focusing on the solutions identified to satisfy the stringent requirements. We briefly illustrate the various phases of the cryostat commissioning and highlight the relevant steps and milestones achieved each time. Finally, we describe the successful cooldown of CUORE.
We estimate the amount of 37Ar produced in natural xenon via cosmic-ray-induced spallation, an inevitable consequence of the transportation and storage of xenon on the Earth’s surface. We then ...calculate the resulting 37Ar concentration in a 10-tonne payload (similar to that of the LUX-ZEPLIN experiment) assuming a representative schedule of xenon purification, storage, and delivery to the underground facility. Using the spallation model by Silberberg and Tsao, the sea-level production rate of 37Ar in natural xenon is estimated to be 0.024 atoms/ kg/day . Assuming the xenon is successively purified to remove radioactive contaminants in 1-tonne batches at a rate of 1 tonne/month, the average 37Ar activity after 10 tons are purified and transported underground is 0.058 - 0.090 μBq/kg , depending on the degree of argon removal during above-ground purification. Such cosmogenic 37Ar will appear as a noticeable background in the early science data, while decaying with a 35-day half-life. This newly noticed production mechanism of 37Ar should be considered when planning for future liquid-xenon-based experiments.
Neutrinoless double-beta (0vββ) decay is a hypothesized lepton-number-violating process that offers the only known means of asserting the possible Majorana nature of neutrino mass. The Cryogenic ...Underground Observatory for Rare Events (CUORE) is an upcoming experiment designed to search for 0vββ decay of sup.130Te using an array of 988 TeO.sub.2 crystal bolometers operated at 10 mK. The detector will contain 206 kg of sup.130Te and have an average energy resolution of 5 keV; the projected 0vββ decay half-life sensitivity after five years of livetime is 1.6 x 10.sup.26 γ at 1σ (9.5 x 10.sup.25 γ at the 90% confidence level), which corresponds to an upper limit on the effective Majorana mass in the range 40-100 meV (50-130 meV). In this paper, we review the experimental techniques used in CUORE as well as its current status and anticipated physics reach.
Low energy analysis techniques for CUORE Alduino, C.; Avignone, F. T.; Azzolini, O. ...
The European physical journal. C, Particles and fields,
12/2017, Letnik:
77, Številka:
12
Journal Article
Recenzirano
Odprti dostop
CUORE is a tonne-scale cryogenic detector operating at the Laboratori Nazionali del Gran Sasso (LNGS) that uses tellurium dioxide bolometers to search for neutrinoless double-beta decay of
130
Te. ...CUORE is also suitable to search for low energy rare events such as solar axions or WIMP scattering, thanks to its ultra-low background and large target mass. However, to conduct such sensitive searches requires improving the energy threshold to 10 keV. In this paper, we describe the analysis techniques developed for the low energy analysis of CUORE-like detectors, using the data acquired from November 2013 to March 2015 by CUORE-0, a single-tower prototype designed to validate the assembly procedure and new cleaning techniques of CUORE. We explain the energy threshold optimization, continuous monitoring of the trigger efficiency, data and event selection, and energy calibration at low energies in detail. We also present the low energy background spectrum of CUORE-0 below
60
keV
. Finally, we report the sensitivity of CUORE to WIMP annual modulation using the CUORE-0 energy threshold and background, as well as an estimate of the uncertainty on the nuclear quenching factor from nuclear recoils inCUORE-0.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The CUORE Cryostat D’Addabbo, A.; Alduino, C.; Bersani, A. ...
Journal of low temperature physics,
12/2018, Letnik:
193, Številka:
5-6
Journal Article
Recenzirano
Odprti dostop
The Cryogenic Underground Observatory for Rare Events (CUORE) is a bolometric experiment for neutrinoless double-beta decay in
130
Te
search, currently taking data at the underground facility of ...Laboratori Nazionali del Gran Sasso (LNGS). The CUORE cryostat successfully cooled down a mass of about 1 ton at
∼
7
mK
, delivering a uniform and constant base temperature. This result marks a fundamental milestone in low-temperature detector techniques, opening the path for future ton-scale bolometric experiments searching for rare events. In this paper, we present the CUORE cryogenic infrastructure, briefly describing its critical subsystems.
The Cryogenic Underground Observatory for Rare Events (CUORE) experiment is presently in the final phases of its commissioning at the Gran Sasso Underground Laboratory (Italy). The CUORE cryogenic ...system will have to guarantee the optimal operation temperature of the detector (∼ 10 mK) for a live-time of 5 years. Furthermore, to avoid radioactive background, about 7 tonnes of lead are cooled to below 4 K and only few construction materials are acceptable. The CUORE detector will be by far the largest mass ever cooled to 10 mK. A description of the CUORE cryostat is presented and the specific characteristics and the performances are illustrated. The results of the (recently concluded) cryostat commissioning are also reported. They show that the CUORE cryostat is now ready to host the detector, thus confirming the possibility of realizing large bolometric arrays for rare event physics.
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