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Crimine e società nel terzo millennio
Get PDFQuali sono gli scenari criminosi del Terzo Millennio? È possibile impiegare gli assiomi delle tradizionali teorie sociali della criminalità per interpretare i fenomeni devianti contemporanei? Con l’intento di fornire una possibile risposta a tali quesiti, si indaga il rapporto esistente tra criminalità e globalizzazione, l’attuale paradigma socio-economico, mediante il modello analitico del Case Study. A partire dall’inquadramento del reato come «fatto sociale» di durkheimiana memoria, seguìto da un sommario richiamo ai contributi teorici in materia, si esaminano i principali indicatori del mercato globale riportati in letteratura, evidenziandone le correlazioni in termini devianti e criminosi. Emergerà con chiarezza come la realtà globale produca nuove forme di criminalità, oltre a riverberarsi su quelle già esistenti, tanto da imporre innovativi modelli di ricerca nell’analisi e nella formulazione di teorie criminologiche adeguate ad un contesto socio-economico in continua evoluzione
SiC detectors for nuclear fragment identification in heavy-ion collisions
No full textThree different configurations of ΔE-E telescopes featuring SiC (Silicon Carbide) detectors have been employed for the identification of nuclear fragments produced in the 40,48Ca+12C interaction at 40 A MeV. Both the ΔE-E and PSA (Pulse Shape Analysis) techniques have been applied, and their results are here presented. The performance of the SiC detector prototypes in terms of identification capability is found to be comparable to that of state-of-the-art silicon
detectors
Small-scale magnetic reconnection during flux emergence in active regions observed in the solar atmosphere
No full textMagnetic reconnection is a fundamental physical process that is thought to occur in a variety of astrophysical environments, appearing to be responsible for sudden energy release phenomena. A plethora of small-scale energetic events have been discovered in the solar atmosphere, most of them linked to magnetic reconnection episodes. Here, we report on the late phases of a reconnection event, which led to the appearance of a long-lasting ultraviolet burst with coronal signatures, observed during flux emergence in the plage of an active region. In particular, we study the final jet ejections and violent eruptions, resembling mini-CMEs
Processing of non-constant baseline pulses: A matrix technique
No full textFor a high source activity experiment, such as HOLMES, nonconstant baseline pulses could constitute a great fraction of the data-set. We test the optimal filter matrix technique, proposed to process these pulses, on simulated responses of HOLMES microcalorimeters
Organic compounds for rare events physics
No full textThe neutrinoless double-beta decay background in TeO2 calorimetric searches receives two main contributions. One comes from α surface contamination and the other is mainly due to 2615 keV γ’s, from the 232Th chain, scattering
Compton with materials close to the detectors. In order to reduce the latter γ component, we propose to replace the usual copper holders with structures made of light organic compounds. A polymethylmethacrylate (PMMA) holder, containing small TeO2 crystals, is operated in a cryogenic setup, together with a similar assembly made of copper. The former registers a lower background in the Region of Interest (RoI), when exposed to a 232Th source, with a 3.8 σ significance. The background reduction of the setup is in agreement with Monte Carlo simulations at 1.2 σ. Then, a more realistic application is considered by simulating the inner CUORE experiment structure made of PMMA. We obtain a γ background reduction factor of 4.7+0.5 −0.6 for photons coming from environmental sources and 5.0+0.1 −0.2 for near detector contaminations with respect to the same setup made of copper
First direct detection of CNO neutrinos: The multivariate fitting strategy
No full textBorexino is a large organic liquid scintillator detector with unprecedented level of radiopurity, located at the LNGS in Italy. Designed for real-time solar neutrino spectroscopy, during more than ten years data collection Borexino measured all the neutrino fluxes produced in the pp chain. The last stages of its life were devoted to the first experimental detection of neutrinos emitted from the CNO cycle. In the following, the detection strategy and the main results will be presented
Compressive tests of a graphite used in devices for the production of radioactive beams
No full textSPES (Selective Production of Exotic Species) is an INFN project in advanced construction phase at Legnaro National Laboratories (Padua). The project is aimed at the construction of a facility for the production of radioactive ion beams, for physical and medical research. Due to the severe conditions that will be achieved during operation, owing to the high temperature and severe stresses, graphite is chosen for designing several devices. Experimental tests have been performed to assess the compressive strength of this material with temperature. The tests showed that as temperature increases, the compressive strength increases: at 2000 ◦C there was an average increase of 22% over its room temperature value. Moreover, as the density increases, the strength increases
Training collective variables for enhanced sampling via neural networks based discriminant analysis
No full textA popular way to accelerate the sampling of rare events in molecular dynamics simulations is to introduce a potential that increases the fluctuations of selected collective variables. For this strategy to be successful, it is critical to choose appropriate variables. Here we review some recent developments in the data-driven design of collective variables, which combine Fisher’s discriminant analysis and neural networks. This approach allows to compress the fluctuations of metastable states into a low-dimensional representation. We illustrate through different applications the effectiveness of this method in accelerating the sampling, while also identifying the physical descriptors that undergo the most significant changes in the process
Use of Monte Carlo simulations for uncertainty evaluation: A proposed approach for a challenging issue in the dosimetry of high dose per pulse electron beams using plane-parallel chambers
No full textThis paper describes a Monte Carlo (MC) approach to assess the ion recombination correction, ks and its associated uncertainty, u(ks), in planeparallel chambers used in high dose-per-pulse electron beam dosimetry. The proposed method was applied to assess ks and u(ks) as a function of the ratio Q1/Q2, i.e., the charge collected at polarizing voltages V1 and V2, in a plane-parallel chamber with electrode spacing = 2 mm. Data were fitted to a general quadratic function with the aim to derive an analytical equation for easy and direct computation of ks and u(ks) in clinical dosimetr
Morphometric analysis of Middle Stone Age tanged tools from South-Western Libya, central Sahara. A regional perspective
Get PDFMorphometric characters of Middle Stone Age stone artefacts from SW Fezzan (Libya, Central Sahara) are investigated. The raw data set is composed of illustrations of tanged pieces from surface scatters and from one stratified and dated site. Both metric and shape analyses are used. The first is carried out on the basis of maximum artefact width and tang width from the whole data set; the second adopts Elliptical Fourier descriptors obtained from 2D contours of tanged points. The geospatial analysis of morphometric variability in a regional perspective shows some meaningful variations between artefacts coming from ‘highland’ and ‘lowland’ physiographic contexts. While the latter encompass most of the regional variability, the former seem to show a narrower range of variation, which could depend on a number of reasons including diverse chronology of occupation, different technological traditions or ecological constraints. The general data patterning is here interpreted in the light of the hypothesis that the water resources kept by the mountainous areas also under environmental stress possibly allowed them to act as a refugium during the most arid phases of the late Pleistocene. An intense occupation of the lowlands during similar chronological time frames and environmental conditions is less likely because of an inferable lower carrying capacity. The regional artefacts’ morphometric variability could thus mirror the population dynamics reconstructed so far for the study area: the record from the mountain ranges testifies for a residual occupation of humans skilled in arid survival, while the lowlands possibly hosted more varied population dynamics especially during cyclically earlier wetter conditions