Two-neutrino double
β
decay can create an irremovable background even in high energy resolution detectors searching for neutrinoless double
β
decay due to random coincidence of 2
ν
2
β
events in the ...case of poor time resolution. Some possibilities for suppressing this background in cryogenic scintillating bolometers are discussed. It is shown that the present bolometric detector technologies enable one to control this form of background at the level required to explore the inverted hierarchy of the neutrino mass pattern, including the case of bolometers searching for the neutrinoless double
β
decay of
100
Mo, which is characterized by a relatively short two-neutrino double
β
decay half-life.
Random coincidence of events (particularly from two neutrino double beta decay) could be one of the main sources of background in the search for neutrinoless double beta decay with cryogenic ...bolometers due to their poor time resolution. Pulse-shape discrimination by using front edge analysis, mean-time and
χ
2
methods were applied to discriminate randomly coinciding events in ZnMoO
4
cryogenic scintillating bolometers. These events can be effectively rejected at the level of 99 % by the analysis of the heat signals with rise-time of about 14 ms and signal-to-noise ratio of 900, and at the level of 92 % by the analysis of the light signals with rise-time of about 3 ms and signal-to-noise ratio of 30, under the requirement to detect 95 % of single events. These rejection efficiencies are compatible with extremely low background levels in the region of interest of neutrinoless double beta decay of
100
Mo for enriched ZnMoO
4
detectors, of the order of
10
-
4
counts/(y keV kg). Pulse-shape parameters have been chosen on the basis of the performance of a real massive ZnMoO
4
scintillating bolometer. Importance of the signal-to-noise ratio, correct finding of the signal start and choice of an appropriate sampling frequency are discussed.
Speleothem inclusions have been identified in a ceramic class, ‘flared rim and flat lip’ pottery, that is widespread in the Friuli – Venetia Giulia and Veneto regions (north‐eastern Italy) between ...the Final Bronze Age and the Early Iron Age. Textural analysis of speleothem inclusions revealed small rounded pores occurring along annual growth laminae, interpreted as the result of partial calcite decomposition during firing. Their size, number and diffusion at increasing temperatures were monitored during a set of firing experiments following heating and cooling rates, soaking times and redox conditions typical of open‐firing kilns. The textural features of the speleothem inclusions turned out to represent a powerful thermometric tool to precisely determine firing temperature which, in the case of the ‘flared rim and flat lip’ pottery studied here, reduced the thermal interval to a greater extent than that obtained from mineralogical associations.
Healthy Stadia (HS) is a European public health pilotprogram started in 2007 to support sports stadia in promoting the health of people who work and visit sports stadia, as well as inhabitants of the ...surrounding communities. The aim of this study is to describe the process evaluation of the program, from its beginning in July 2007 to December 2009, in order to assess the feasibility and sustainability of an HS network across Europe. The program involved nine associate partners involved in the coordination of activities at a local level, in the recruitment of stadia, in the development of specific program tasks and in the dissemination of the program at a national level. The activities of associate partners were evaluated through structured questionnaires administered every 6 months. The questionnaire response rate from associate partners was 77.8% for the first and third evaluations and 88.9% for the second and fourth evaluations. According to the evaluation’s results, several good practices such as alcohol prevention policies and those supporting people with disabilities were implemented in stadia over the course of the program. Conversely, practices supporting mental health and green transport were generally not achieved. The implemented activities mainly involved staff and visitors. Lack of human and economic resources, especially toward the end of the program, was considered the principal challenge for program development. In conclusion, the process evaluation presented the feasibility of the HS program and the development of health promoting practices in sport stadia over time.
Zinc molybdate (ZnMoO4) crystals are an excellent candidate material to fabricate scintillating bolometers for the study of neutrinoless double beta decay of 100Mo, provided that the crystal quality ...meets strict optical, thermal and radiopurity requirements. This paper addresses the characterization of improved crystalline samples grown by the low-thermal-gradient Czochralski technique. Transmittance measurements confirm significant improvement of the material with respect to previously developed samples. Luminescence properties (emission spectra, dependence of intensity on temperature, thermally stimulated luminescence and phosphorescence) have been studied under X-ray excitation from liquid-helium to room temperature. The index of refraction was measured in the wavelength interval 406–655nm. Samples of ZnMoO4 crystals with masses of 5.07g and 23.8g were operated as scintillating bolometers at temperatures below 30mK, with simultaneous detection of scintillation and heat signals, confirming an excellent alpha/beta rejection power. Background measurements allowed encouraging radiopurity level estimations. The light collection from ZnMoO4 scintillators was Monte Carlo simulated, analysing different crystal size, shape and surface properties and different photodetector sizes.
In the field of fundamental particle physics, the neutrino has become more and more important in the last few years, since the discovery of its mass. In particular, the ultimate nature of the ...neutrino (if it is a Dirac or a Majorana particle) plays a crucial role not only in neutrino physics, but also in the overall framework of fundamental particle interactions and in cosmology. The only way to disentangle its ultimate nature is to search for the neutrinoless double beta decay. The idea of LUCIFER is to combine the bolometric technique proposed for the CUORE experiment with the bolometric light detection technique used in cryogenic dark matter experiments. The bolometric technique allows an extremely good energy resolution while its combination with the scintillation detection offers an ultimate tool for background rejection. The goal of LUCIFER is not only to build a background-free small-scale experiment but also to directly prove the potentiality of this technique. Preliminary tests on several detectors containing different interesting DBD emitters have clearly demonstrated the excellent background rejection capabilities that arise from the simultaneous, independent, double readout of heat and scintillation light.
In many relevant cases requiring a net energy comparable with that of a household appliance, the power supplies (PSs) and the electrical systems must be oversized to sustain short peak demands. The ...same equivalent energy could be achieved by storing and distributing the power over the time. These considerations lead to a new PS concept based on the exploitation of the energy stored between the actual operations. The new compact (<inline-formula> <tex-math notation="LaTeX">60\,\,\text {cm} \times 120\,\,\text {cm} \times 190 </tex-math></inline-formula> cm) PS is able to generate arbitrary currents up to 2 kA by an integrated energy storage system based on supercapacitors. The delivered output power (approximately 200 kW) is obtained from a very low and tunable input power (<1 kW). Furthermore, a portion of the injected power can be recovered in the storage system. Even though the system was designed for a specific project (the PROTO-SPHERA spherical tokamak), the presented approach can be applied to general-purpose PSs, and there are encouraging prospects to extend it to large facilities with higher currents and voltages.
Objective: To determine: (a) whether the components of metabolic syndrome (MetS) cluster more frequently than predicted by chance alone and (b) whether increased risk for MetS is associated also with ...values of each component below, but close to the cutoff points defining MetS. Research design and methods: Anthropometrical and biochemical measurements were performed and a dietary questionnaire was filled-in in 1833 randomly selected non-diabetic subjects, 916 men and 917 women, 20-74 years old, in nine centres in five Mediterranean countries. The prevalence of MetS and of possible combinations of its individual components was measured. The expected frequencies of the above combinations were calculated according to the mathematical formula of probabilities. Results: The overall prevalence of MetS was 27.2%, but varied greatly among countries, from 5.8% in Algeria to 37.3% in Greece. The observed prevalence of each combination diagnostic of MetS was higher than the expected by chance. Thus, the observed overall prevalence of MetS was also higher than the expected, 27.2 vs 24.0%, P=0.03. Furthermore, for each individual component (except high-density lipoprotein), as values in the normal range, approached the cutoff point, the risk of having MetS (i.e. clustering of the other components) increased significantly (odds ratio 2.2-4.6, P<0.001). Conclusions: The MetS is not related to the Mediterranean type of diet and its prevalence varies greatly among five Mediterranean countries. The clustering of the components defining the MetS is not due to chance and moreover even 'high normal' levels of each component confer increased risk for the syndrome.
The LUMINEU project aims at developing a pilot double beta decay experiment using scintillating bolometers based on ZnMoO \(_4\) crystals enriched in \(100}\hbox {Mo}\) . In the next months regular ...deliveries of large-mass \(\hbox {ZnMoO}_4\) crystals are expected from the Nikolaev Institute of Inorganic Chemistry (Novosibirsk, Russia). It is therefore crucial for the LUMINEU program to test systematically and in real time these samples in terms of bolometric properties, light yield and internal radioactive contamination. In this paper we describe an aboveground cryogenic facility based on a dilution refrigerator coupled to a pulse-tube cooler capable performing these measurements. A 23.8 g \(\hbox {ZnMoO}_4\) crystal was fully characterised in this setup. We show also that macro-bolometers can be operated with high signal-to-noise ratio in liquid-free dilution refrigerators.
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