The CUORE Cryostat: A 1-Ton Scale Setup for Bolometric Detectors

The cryogenic underground observatory for rare events (CUORE) is a 1-ton scale bolometric experiment whose detector consists of an array of 988 TeO2 crystals arranged in a cylindrical compact structure of 19 towers. This will be the largest bolometric mass ever operated. The experiment will work at a temperature around or below 10 mK. CUORE cryostat consists of a cryogen-free system based on pulse tubes and a custom high power dilution refrigerator, designed to match these specifications. The cryostat has been commissioned in 2014 at the Gran Sasso National Laboratories and reached a record temperature of 6 mK on a cubic meter scale. In this paper, we present results of CUORE commissioning runs. Details on the thermal characteristics and cryogenic performances of the system will be also given.Comment: 7 pages, 2 figures, LTD16 conference proceedin

Marginal zone lymphomas in children and the young adult population; characterization of genetic aberrations by FISH and RT-PCR

Marginal zone lymphomas present rarely in children and young adults as either primary nodal or extranodal disease and have an excellent prognosis. To date, chromosomal aberrations have not been analyzed in the pediatric and young adult population. We undertook a study to analyze genetic alterations in nodal and extranodal marginal zone lymphomas in children and young adults using fluorescence in situ hybridization (FISH) and RT-PCR. These findings were correlated with clinical features at presentation and immunophenotype. Forty-one cases were identified meeting these criteria. The age range was 1.5-29 years old with 49% of the cases <18 years of age. 73% of the marginal zone lymphoma cases showed evidence of light chain restriction by immunohistochemistry or flow cytometry. CD43 was coexpressed in 83%. 85% of the marginal zone lymphoma cases tested showed evidence of immunoglobulin heavy chain gene rearrangement. Fifty-nine percent of the cases were nodal marginal zone lymphomas with a median age at presentation of 16 years and an M/F ratio of 7:1. Twenty-one percent of the nodal marginal zone lymphoma cases contained genetic aberrations. Seventeen percent contained trisomy 18 with one case containing an additional trisomy 3. A translocation of the immunoglobulin heavy chain gene to an unknown partner gene was present in one case. Forty-one percent of the cases were extranodal marginal zone lymphomas with a median age of 24 years and a M/F ratio of 1.4:1. Eighteen percent of the extranodal marginal zone lymphoma cases contained genetic aberrations. The t(14;18) involving the IGH and MALT1 genes was present in one case, tetraploidy was present in one case, and another case contained trisomy 3. Overall the incidence of genetic aberrations in marginal zone lymphomas in the pediatric and young adult population is low, but the aberrations seen are similar to those seen in the adult population

Annealing Characteristics Of Neutron Irradiated Silicon Transistors

When a transistor is subjected to neutron irradiation, a component of base current proportional to neutron fluence is induced. From the effects of annealing on the base and collector Currents the conclusion was drawn that there is an apparent difference in the annealing characteristics between the neutral and the space-charge regions of the semiconductor device. This study of the anomalous annealing indicates that the neutron-induced component of base current is a result of one, or a combination, of the following mechanisms: A quasi-tunneling recombination phenomena in the emitter-base space-charge region, or an influence of the p-n junction electric field on the formation, annealing, and electronic behavior of the neutron-induced defect centers. A field dependence of the formation and annealing of the neutron-induced defects appears to be present both during the introduction and annealing of the neutron-induced defect centers. It could not be finally determined whether or not the quasi-tunneling phenomena occurred although it can be shown on theoretical grounds that it is possible for such phenomena to occur. The annealing characteristics of the defects, as represented by changes in the collector and base currents, have been obtained. Three sets of devices were irradiated and then annealed, with one set having a forward bias during annealing, one set having no bias, and one set having a reverse bias. The dependence of the field on annealing is present but appears quite complex. The presence of the externally applied electric field during annealing appears to influence the annealing of neutron-induced defects similarly, regardless of whether the junction is forward or reverse biased. Copyright © 1967 by The Institute of Electrical and Electronics Engineers, Inc

Simulations of events for the LUX-ZEPLIN (LZ) dark matter experiment

The LUX-ZEPLIN dark matter search aims to achieve a sensitivity to the WIMP-nucleon spin-independent cross-section down to (1–2)×10−12 pb at a WIMP mass of 40 GeV/c2. This paper describes the simulations framework that, along with radioactivity measurements, was used to support this projection, and also to provide mock data for validating reconstruction and analysis software. Of particular note are the event generators, which allow us to model the background radiation, and the detector response physics used in the production of raw signals, which can be converted into digitized waveforms similar to data from the operational detector. Inclusion of the detector response allows us to process simulated data using the same analysis routines as developed to process the experimental data

BMC Gastroenterology / Follow-up of pediatric celiac disease: value of antibodies in predicting mucosal healing, a prospective cohort study

Background: In diagnosing celiac disease (CD), serological tests are highly valuable. However, their role in following up children with CD after prescription of a gluten-free diet is unclear. This study aimed to compare the performance of antibody tests in predicting small-intestinal mucosal status in diagnosis vs. follow-up of pediatric CD. Methods: We conducted a prospective cohort study at a tertiary-care center. 148 children underwent esophohagogastroduodenoscopy with biopsies either for symptoms \ub1 positive CD antibodies (group A; n = 95) or following up CD diagnosed 65 1 year before study enrollment (group B; n = 53). Using biopsy (Marsh 65 2) as the criterion standard, areas under ROC curves (AUCs) and likelihood-ratios were calculated to estimate the performance of antibody tests against tissue transglutaminase (TG2), deamidated gliadin peptide (DGP) and endomysium (EMA). Results: AUCs were higher when tests were used for CD diagnosis vs. follow-up: 1 vs. 0.86 (P = 0.100) for TG2-IgA, 0.85 vs. 0.74 (P = 0.421) for TG2-IgG, 0.97 vs. 0.61 (P = 0.004) for DPG-IgA, and 0.99 vs. 0.88 (P = 0.053) for DPG-IgG, respectively. Empirical power was 85% for the DPG-IgA comparison, and on average 33% (range 13\u201343) for the non-significant comparisons. Among group B children, 88.7% showed mucosal healing (median 2.2 years after primary diagnosis). Only the negative likelihood-ratio of EMA was low enough (0.097) to effectively rule out persistent mucosal injury. However, out of 12 EMA-positive children with mucosal healing, 9 subsequently turned EMA-negative. Conclusions: Among the CD antibodies examined, negative EMA most reliably predict mucosal healing. In general, however, antibody tests, especially DPG-IgA, are of limited value in predicting the mucosal status in the early years post-diagnosis but may be sufficient after a longer period of time

Search for 14.4 keV solar axions from M1 transition of Fe-57 with CUORE crystals

We report the results of a search for axions from the 14.4 keV M1 transition from Fe-57 in the core of the sun using the axio-electric effect in TeO2 bolometers. The detectors are 5x5x5 cm3 crystals operated at about 10 mK in a facility used to test bolometers for the CUORE experiment at the Laboratori Nazionali del Gran Sasso in Italy. An analysis of 43.65 kg d of data was made using a newly developed low energy trigger which was optimized to reduce the detectors energy threshold. An upper limit of 0.63 c kg-1 d-1 was established at 95% C.L.. From this value, a lower bound at 95% C.L. was placed on the Peccei-Quinn energy scale of fa >= 0.76 10**6 GeV for a value of S=0.55 for the flavor-singlet axial vector matrix element. Bounds are given for the interval 0.15 < S < 0.55.Comment: 14 pages, 6 figures, submitted to JCA

Exploring the Neutrinoless Double Beta Decay in the Inverted Neutrino Hierarchy with Bolometric Detectors

Neutrinoless double beta decay (0nubb) is one of the most sensitive probes for physics beyond the Standard Model, providing unique information on the nature of neutrinos. In this paper we review the status and outlook for bolometric 0nubb decay searches. We summarize recent advances in background suppression demonstrated using bolometers with simultaneous readout of heat and light signals. We simulate several configurations of a future CUORE-like bolometer array which would utilize these improvements and present the sensitivity reach of a hypothetical next-generation bolometric 0nubb experiment. We demonstrate that a bolometric experiment with the isotope mass of about 1 ton is capable of reaching the sensitivity to the effective Majorana neutrino mass (|mee|) of order 10-20 meV, thus completely exploring the so-called inverted neutrino mass hierarchy region. We highlight the main challenges and identify priorities for an R&D program addressing them.Comment: 22 pages, 15 figures, submitted to EPJ

Search for Neutrinoless Double-Beta Decay of 130^{130}Te with CUORE-0

We report the results of a search for neutrinoless double-beta decay in a 9.8~kg$\cdot$yr exposure of $^{130}$Te using a bolometric detector array, CUORE-0. The characteristic detector energy resolution and background level in the region of interest are $5.1\pm 0.3{\rm~keV}$ FWHM and $0.058 \pm 0.004\,(\mathrm{stat.})\pm 0.002\,(\mathrm{syst.})$~counts/(keV$\cdot$kg$\cdot$yr), respectively. The median 90%~C.L. lower-limit sensitivity of the experiment is $2.9\times 10^{24}~{\rm yr}$ and surpasses the sensitivity of previous searches. We find no evidence for neutrinoless double-beta decay of $^{130}$Te and place a Bayesian lower bound on the decay half-life, $T^{0\nu}_{1/2}>$~$2.7\times 10^{24}~{\rm yr}$ at 90%~C.L. Combining CUORE-0 data with the 19.75~kg$\cdot$yr exposure of $^{130}$Te from the Cuoricino experiment we obtain $T^{0\nu}_{1/2} > 4.0\times 10^{24}~\mathrm{yr}$ at 90%~C.L.~(Bayesian), the most stringent limit to date on this half-life. Using a range of nuclear matrix element estimates we interpret this as a limit on the effective Majorana neutrino mass, $m_{\beta\beta}< 270$ -- $760~\mathrm{meV}$.Comment: 6 pages, 5 figures, updated version as published in PR