Performance comparison between signal digitizers and low-cost digital oscilloscopes: spectroscopic, pulse shape discrimination and timing capabilities for nuclear detectors

Signal digitizers revolutionized the approach to the electronics readout of radiation detectors in Nuclear Physics. These highly specialized pieces of equipment are designed to acquire the signals that are characteristic of the detectors in nuclear physics experiments. The functions of the several modules that were once needed for signal acquisition, can now be substituted by a single digitizer. As suggested by the name, with such readout modules, signals are first digitized (i.e. the signal waveform is sampled and converted to a digital representation) and then either stored or analyzed on-the-fly. The performances can be comparable or better than the traditional analog counterparts, in terms of energy, time resolution, and acquisition rate. In this work, we investigate the use of general-purpose digital oscilloscopes as signal digitizers for nuclear detectors. In order to have a proper comparison, we employ a distributed data acquisition system (DAQ), that standardizes the interface between the hardware and the on-line data analysis. The signals, from a set of typical radiation detectors, are digitized and analyzed with the very same algorithms in order to avoid biases due to different software analysis. We compare two traditional signal digitizers (CAEN DT5725 and CAEN DT5751) to two low-cost digital oscilloscopes (Digilent Analog Discovery 2, and Red Pitaya STEMLab 125-14), in terms of their capabilities for spectroscopy (energy resolution), time resolution, pulse shape discrimination, and maximum acquisition rate.Comment: 17 pages, 8 figures, 4 tables, Prepared for submission to JINS

Cotidiano escolar: algumas reflexões sobre a prática do estágio na formação do professor de geografia

O presente artigo traz reflexões a partir da prática de estágio que é uma atividade essencial para a formação do professor pois possibilita uma inserção no seu campo de trabalho e amplia as possibilidades de pesquisas na área da educação e ensino de geografia. O estágio em questão foi realizado nas aulas de geografia no ensino fundamental II e teve o foco nos marcos legais e nas políticas curriculares e seus desdobramentos no âmbito escolar através do ciclo de políticas de Ball e Bowe. Além das questões políticas este artigo traz reflexões sobre os obstáculos presentes  na prática docente e suas problemáticas, como as avaliações externas, o uso do livro didático e a exclusão na escola. Por fim, apresenta as ressignificações do contexto escolar com pouco caráter transformador, legitimando a escola no contexto da qual foi formulada

a distributed data acquisition system for nuclear detectors

Nowadays, many examples of data acquisition (DAQ) software for experimental nuclear physics are monolithic processes that run on a computer attached to the DAQ hardware. In this article we present a distributed DAQ system developed for the C-BORD project. With our system, we propose a novel approach, in which each task related to the different DAQ parts (acquisition, pre-process, analysis, etc.) runs in a separate process. In particular, the system is composed of a set of servers that exchange information through dedicated communication sockets. Therefore, with this architecture, an important advantage is the possibility to run the processes on different computers to distribute the computational load. The initial tests of the system have been giving excellent results, both in terms of performance (i.e., maximum acquisition rates) and stability. The project entitled "Effective container inspection at BORDer control points" (C-BORD) is funded by the European H2020 programme. Its aim is to develop a comprehensive set of technologies for the generalized non-intrusive inspection (NII) of containers and large-volume freight at the European Union border

Material recognition with a 252Cf source

Material recognition is studied by measuring simultaneously the transmission of neutron and gamma rays produced by a time-tagged 252Cf source. Light elements (C,N,O) are identified by using the measured transmission versus neutron time of flight. The yield of the transmitted gamma ray as a function of energy provides high precision identification of the atomic number of the sample up to Z=83 . A tomography system, currently under construction, is described

The effect of customer perceived value on customer satisfaction: a case study of Malay upscale restaurants

Stiff competition and increasingly high operating costs have driven many international and domestic players to introduce new outlet concepts. Malay fine dining, upscale restaurant segment is gaining popularity among Malaysian, especially in Kuala Lumpur. This study examined the effect of perceived value on customer satisfaction in Malay upscale restaurants in terms of emotional responses, monetary prices, behavioral price and reputation. Primary data were gathered from 170 questionnaires returned by respondents from five Malay upscale restaurants in Kuala Lumpur, and statistically analysed using SPSS version 21. The findings of this study revealed that monetary prices had a high positive relationship with customer satisfaction. In addition, the beta value for emotional responses (β=0.530, p<0.01), behavioral price (β=0.180, p<0.01) and reputation (β=0.168, p<0.01) also indicated the respective contributions made to customer satisfaction

Central and peripheral effects of physical exercise without weight reduction in obese and lean mice

To investigate the central (hypothalamic) and peripheral effects of exercise without body weight change in diet-induced obesity (DIO). Twelve-week-old male C57Bl/6 mice received a control (C) or a high-fat diet (H). Half of them had free access to running wheels for 5 days/week for 10 weeks (CE) and HE, respectively). Hypothalamic expression of genes related to energy homeostasis, and leptin (Stat3 and p-Stat3) and insulin (Akt and p-Akt) signaling were evaluated. Glucose and leptin tolerance, peripheral insulin sensitivity, and plasma insulin, leptin and adiponectin were determined. Perigonadal and retroperitoneal fat depots were increased by diet but reduced by exercise despite lack of effect of exercise on body weight. Blood glucose during intraperitoneal glucose tolerance test (ipGTT) was higher and glucose decay during intraperitoneal insulin tolerance test (ipITT) was lower in H and HE compared with C and CE. Exercise increased liver p-Akt expression and reduced fast glycemia. High-fat diet increased plasma insulin and leptin. Exercise had no effect on insulin but decreased leptin and increased adiponectin. Leptin inhibited food intake in all groups. Hypothalamic total and p-Stat3 and Akt were similar amongst the groups despite higher plasma levels of leptin and insulin in H and HE mice. High-fat diet modulated gene expression favoring a positive energy balance. Exercise only marginally changed the gene expression. Exercise induced positive changes (decreased fast glycemia and fat depots; increased liver insulin signaling and adiponectin concentration) without weight loss. Thus, despite reducing body weight could bring additional benefits, the effects of exercise must not be overlooked when weight reduction is not achieved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Univ Fed Sao Paulo, Programa Posgrad Interdisciplinar Ciencias Saude, Santos, SP, BrazilUniv Fed Sao Paulo, Programa Posgrad Alimentos Nutr & Saude, Santos, SP, BrazilUniv Estadual Campinas Unicamp, Inst Biol, Dept Biol Func & Estrutural, Campinas, SP, BrazilUniv Fed Sao Paulo, Inst Saude & Soc, Dept Biociencias, Santos, SP, BrazilUniv Fed Sao Paulo, Programa Posgrad Interdisciplinar Ciencias Saude, Santos, SP, BrazilUniv Fed Sao Paulo, Programa Posgrad Alimentos Nutr & Saude, Santos, SP, BrazilUniv Fed Sao Paulo, Inst Saude & Soc, Dept Biociencias, Santos, SP, BrazilFAPESP: 2011/05932-3FAPESP: 2013/01624-8Web of Scienc

The ALICE Silicon Pixel Detector System (SPD)

The ALICE silicon pixel detector (SPD) comprises the two innermost layers of the ALICE inner tracker system. The SPD includes 120 detector modules (half-staves) each consisting of 10 ALICE pixel chips bump bonded to two silicon sensors and one multi-chip read-out module. Each pixel chip contains 8192 active cells, so that the total number of pixel cells in the SPD is ≈ 107. The on-detector read-out is based on a multi-chip-module containing 4 ASICs and an optical transceiver module. The constraints on material budget and detector module dimensions are very demanding

NEW EXPERIMENTAL APPROACH FOR HEAVY AND SUPERHEAVY ELEMENT PRODUCTION

In this article we present a new experimental approach for production of heavy and superheavy elements (HE, SHE). Nuclear reactions at low incident energies induced by heavy ion (HI) projectiles on fissile target nuclei are investigated. Dedicated detection setup is presented and the preliminary results for the reaction 197Au(7.5 MeV /u) + 232Th, studied at the Cyclotron Institute of Texas A&M University, are given

A Proton Recoil Telescope for Neutron Spectroscopy

The N2P research program funded by the INFN committee for Experimental Nuclear Physics (CSNIII) has among his goals the construction of a Proton Recoil Telescope (PRT), a detector to measure neutron energy spectra. The interest in such a detector is primarily related to the SPES project for rare beams production at the Laboratori Nazionali di Legnaro. For the SPES project it is, in fact, of fundamental importance to have reliable information about energy spectra and yield for neutrons produced by d or p projectiles on thick light targets to model the ''conversion target'' in which the p or d are converted in neutrons. These neutrons, in a second stage, will induce the Uranium fission in the ''production target''. The fission products are subsequently extracted, selected and re-accelerated to produce the exotic beam. The neutron spectra and angular distribution are important parameters to define the final production of fission fragments. In addition, this detector can be used to measure neutron spectra in the field of cancer therapy (this topic is nowadays of particular interest to INFN, for the National Centre for Hadron therapy (CNAO) in Pavia) and space applications