454 research outputs found

    Detection of K+ mesons in segmented electromagnetic calorimeters

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    The combination of the CrystalBall and TAPS electromagnetic calorimeters were installed in the MAMI A2 hall in 2003. Here they are able to detect the reaction products from photo-induced reactions in combination with the Glasgow photon tagger. In the last two years the MAMI facility was upgraded from 885 MeV to 1.5 GeV, the A2 photon tagger underwent a similar upgrade crossing the threshold for strangeness photoproduction. For the CrystalBall this created a new challenge, to identify K+ mesons above the large background from other charged hadrons, in a situation where the detector setup does not benefit from a magnetic field to help separate particle species. These proceedings outline a novel technique which uses the decay products of the K+ as a strangeness tag

    Suicide screening tools for use in adult offenders: a systematic review

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    Self-inflicted deaths in prisons in England and Wales, recently reported as the highest in over a decade, are a significant cause of mortality. A lack of guidelines surrounding the screening and identification of suicide risk of new prisoners along with a dearth of effective screening tools indicate the need for review. Our aims are to examine findings on the effectiveness of prison specific suicide screening tools used with adult prisoners. Papers were identified via systematic searches of databases, scanning grey literature, and reference checking. Included studies were published over the period between 2000–2016. PRISMA guidelines were followed. Studies were selected based on population – adult imprisoned offenders; intervention – suicide screening tool; comparators – participants screened vs. not screened outcome – suicide or attempted suicide. Data was extracted manually. A narrative synthesis presented the findings between different screening tools. Eight screening tools were critically appraised. Evidence suggested that the VISCI and Dutch screening tools are most effective in identifying those at risk and reducing suicide and/or self-harm behavior. Variance in methodological quality and associated factors indicate the need for further development of prospective studies to develop robust screening tools

    CHEMICAL EQUIVALENT BASE EXCHANGE REACTIONS IN PLANTS

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    Three-nucleon mechanisms in photoreactions

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    The 12^{12}C(γ,ppn)(\gamma,ppn) reaction has been measured for Eγ_{\gamma}=150-800 MeV in the first study of this reaction in a target heavier than 3^3He. The experimental data are compared to a microscopic many body calculation. The model, which predicts that the largest contribution to the reaction arises from final state interactions following an initial pion production process, overestimates the measured cross sections and there are strong indications that the overestimate arises in this two-step process. The selection of suitable kinematic conditions strongly suppresses this two-step contribution leaving cross sections in which up to half the yield is predicted to arise from the absorption of the photon on three interacting nucleons and which agree with the model. The results indicate (γ,3N)(\gamma,3N) measurements on nuclei may be a valuable tool for obtaining information on the nuclear three-body interaction.Comment: 5 pages, 3 figure
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