1,136 research outputs found

    u-RANIA: a neutron detector based on \mu -RWELL technology

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    In the framework of the ATTRACT-uRANIA project, funded by the European Community, we are developing an innovative neutron imaging detector based on micro-Resistive WELL (Ό\mu -RWELL) technology. The Ό\mu -RWELL, based on the resistive detector concept, ensuring an efficient spark quenching mechanism, is a highly reliable device. It is composed by two main elements: a readout-PCB and a cathode. The amplification stage for this device is embedded in the readout board through a resistive layer realized by means of an industrial process with DLC (Diamond-Like Carbon). A thin layer of B4_4C on the copper surface of the cathode allows the thermal neutrons detection through the release of 7^7Li and α\alpha particles in the active volume. This technology has been developed to be an efficient and convenient alternative to the 3^3He shortage. The goal of the project is to prove the feasibility of such a novel neutron detector by developing and testing small planar prototypes with readout boards suitably segmented with strip or pad read out, equipped with existing electronics or readout in current mode. Preliminary results from the test with different prototypes, showing a good agreement with the simulation, will be presented together with construction details of the prototypes and the future steps of the project.Comment: Prepared for the INSTR20 Conference Proceeding for JINS

    The Straw Tube Trackers of the PANDA Experiment

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    The PANDA experiment will be built at the FAIR facility at Darmstadt (Germany) to perform accurate tests of the strong interaction through bar pp and bar pA annihilation's studies. To track charged particles, two systems consisting of a set of planar, closed-packed, self-supporting straw tube layers are under construction. The PANDA straw tubes will have also unique characteristics in term of material budget and performance. They consist of very thin mylar-aluminized cathodes which are made self-supporting by means of the operation gas-mixture over-pressure. This solution allows to reduce at maximum the weight of the mechanical support frame and hence the detector material budget. The PANDA straw tube central tracker will not only reconstruct charged particle trajectories, but also will help in low momentum (< 1 GeV) particle identification via dE/dx measurements. This is a quite new approach that PANDA tracking group has first tested with detailed Monte Carlo simulations, and then with experimental tests of detector prototypes. This paper addresses the design issues of the PANDA straw tube trackers and the performance obtained in prototype tests.Comment: 7 pages,16 figure

    Italian national data bank of stillbirth vs. SIDS.

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    Sudden perinatal death, which includes antepartum death (from 22 completed weeks of gestation), intrapartum death and early neonatal death (occurring within seven completed days of life), and sudden infant death syndrome (SIDS), represents one of the major sociomedical and scientific problems still lacking a solution in today\u2019s medicine.1 However, little effort is being made to find a cause of these deaths, as there is no standard method of performing an autopsy in these victims, and no database exists from which researchers can draw autopsy results. Therefore, the need to submit the young victims to necropsy procedures through a standardized protocol is unanimously recognized, and the chance of preventing perinatal unexpected death and SIDS relies mainly on a better knowledge of the underlying alterations of organs and etiopathogenetic mechanisms. Similarly, for diagnostic purposes, an accurate and careful examination of the circumstantial, environmental, and familial situation within which the death occurred is extremely important. All the information related to victims of sudden and unexplained fetal death and SIDS will soon be made available in Italy through a specific data bank established under the Law 31/2006 \u201cRegulations for Diagnostic Post Mortem Investigation in Victims of Sudden Infant Death Syndrome (SIDS) and Unexpected Fetal Death.\u201d2 This law mandates that infants who die suddenly within one year of life, and fetuses that die after 22 weeks of gestation without any apparent cause, must be rapidly submitted\u2014with the consent of both parents\u2014to diagnostic postmortem investigation.3 Information about the pregnancy, fetal development and delivery, and, in the case of SIDS, the environmental and familial situation in which the death occurred\u2014in addition to information related to risk factors\u2014must be collected by the obstetriciangynecologist, neonatologist, pediatrician, and pathologist involved in the case and recorded in the registry of the data bank. In addition, to facilitate the collection and analysis of the data, this data bank will allow the Lino Rossi Research Center in collaboration with the Epidemiology Center of the Italian National Health Institute to update the population through public education and prevention programs aimed at decreasing the incidence of stillbirth and SIDS

    A straw tube detector for the PANDA experiment

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    The PANDA experiment will be built at the FAIR facility in Darmstadt (Germany) to perform accurate tests of the strong interaction through pp and pA annihilations. This paper will address the design issue of the Straw Tube Tracker (STT), one of the two options proposed for the PANDA Central Tracker

    A model to explain angular distributions of J/ψJ/\psi and ψ(2S)\psi(2S) decays into ΛΛ‟\Lambda\overline{\Lambda} and ÎŁ0ÎŁâ€Ÿ0\Sigma^0\overline{\Sigma}^0

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    BESIII data show a particular angular distribution for the decay of the J/ψJ/\psi and ψ(2S)\psi(2S) mesons into the hyperons ΛΛ‟\Lambda\overline{\Lambda} and ÎŁ0ÎŁâ€Ÿ0\Sigma^0\overline{\Sigma}^0. More in details the angular distribution of the decay ψ(2S)→Σ0ÎŁâ€Ÿ0\psi(2S) \to \Sigma^0\overline{\Sigma}^0 exhibits an opposite trend with respect to that of the other three channels: J/ψ→ΛΛ‟J/\psi \to \Lambda\overline{\Lambda}, J/Ïˆâ†’ÎŁ0ÎŁâ€Ÿ0J/\psi \to \Sigma^0\overline{\Sigma}^0 and ψ(2S)→ΛΛ‟\psi(2S) \to \Lambda\overline{\Lambda}. We define a model to explain the origin of this phenomenon.Comment: 6 pages, 7 figures, to be published in Chinese Physics

    Brain iron accumulation in unexplained fetal and infant death victims with smoker mothers-The possible involvement of maternal methemoglobinemia

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    <p>Abstract</p> <p>Background</p> <p>Iron is involved in important vital functions as an essential component of the oxygen-transporting heme mechanism. In this study we aimed to evaluate whether oxidative metabolites from maternal cigarette smoke could affect iron homeostasis in the brain of victims of sudden unexplained fetal and infant death, maybe through the induction of maternal hemoglobin damage, such as in case of methemoglobinemia.</p> <p>Methods</p> <p>Histochemical investigations by Prussian blue reaction were made on brain nonheme ferric iron deposits, gaining detailed data on their localization in the brainstem and cerebellum of victims of sudden death and controls. The Gless and Marsland's modification of Bielschowsky's was used to identify neuronal cell bodies and neurofilaments.</p> <p>Results</p> <p>Our approach highlighted accumulations of blue granulations, indicative of iron positive reactions, in the brainstem and cerebellum of 33% of victims of sudden death and in none of the control group. The modified Bielschowsky's method confirmed that the cells with iron accumulations were neuronal cells.</p> <p>Conclusions</p> <p>We propose that the free iron deposition in the brain of sudden fetal and infant death victims could be a catabolic product of maternal methemoglobinemia, a biomarker of oxidative stress likely due to nicotine absorption.</p

    A Cylindrical GEM Inner Tracker for the BESIII experiment at IHEP

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    The Beijing Electron Spectrometer III (BESIII) is a multipurpose detector that collects data provided by the collision in the Beijing Electron Positron Collider II (BEPCII), hosted at the Institute of High Energy Physics of Beijing. Since the beginning of its operation, BESIII has collected the world largest sample of J/{\psi} and {\psi}(2s). Due to the increase of the luminosity up to its nominal value of 10^33 cm-2 s-1 and aging effect, the MDC decreases its efficiency in the first layers up to 35% with respect to the value in 2014. Since BESIII has to take data up to 2022 with the chance to continue up to 2027, the Italian collaboration proposed to replace the inner part of the MDC with three independent layers of Cylindrical triple-GEM (CGEM). The CGEM-IT project will deploy several new features and innovation with respect the other current GEM based detector: the {\mu}TPC and analog readout, with time and charge measurements will allow to reach the 130 {\mu}m spatial resolution in 1 T magnetic field requested by the BESIII collaboration. In this proceeding, an update of the status of the project will be presented, with a particular focus on the results with planar and cylindrical prototypes with test beams data. These results are beyond the state of the art for GEM technology in magnetic field

    Technical Design Report for the PANDA Solenoid and Dipole Spectrometer Magnets

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    This document is the Technical Design Report covering the two large spectrometer magnets of the PANDA detector set-up. It shows the conceptual design of the magnets and their anticipated performance. It precedes the tender and procurement of the magnets and, hence, is subject to possible modifications arising during this process.Comment: 10 pages, 14MB, accepted by FAIR STI in May 2009, editors: Inti Lehmann (chair), Andrea Bersani, Yuri Lobanov, Jost Luehning, Jerzy Smyrski, Technical Coordiantor: Lars Schmitt, Bernd Lewandowski (deputy), Spokespersons: Ulrich Wiedner, Paola Gianotti (deputy
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