25 research outputs found

    Microscopic theories of neutrino-^{12}C reactions

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    In view of the recent experiments on neutrino oscillations performed by the LSND and KARMEN collaborations as well as of future experiments, we present new theoretical results of the flux averaged 12C(Îœe,e−)12N^{12}C(\nu_e,e^-)^{12}N and 12C(ΜΌ,Ό−)12N^{12}C(\nu_{\mu},{\mu}^-)^{12}N cross sections. The approaches used are charge-exchange RPA, charge-exchange RPA among quasi-particles (QRPA) and the Shell Model. With a large-scale shell model calculation the exclusive cross sections are in nice agreement with the experimental values for both reactions. The inclusive cross section for ΜΌ\nu_{\mu} coming from the decay-in-flight of π+\pi^+ is 15.2×10−40cm215.2 \times 10^{-40} cm^2 to be compared to the experimental value of 12.4±0.3±1.8×10−40cm212.4 \pm 0.3 \pm 1.8 \times 10^{-40} cm^2, while the one due to Îœe\nu_{e} coming from the decay-at-rest of ÎŒ+\mu^+ is 16.4×10−42cm216.4 \times 10^{-42} cm^2 which agrees within experimental error bars with the measured values. The shell model prediction for the decay-in-flight neutrino cross section is reduced compared to the RPA one. This is mainly due to the different kind of correlations taken into account in the calculation of the spin modes and partially due to the shell-model configuration basis which is not large enough, as we show using arguments based on sum-rules.Comment: 17 pages, latex, 5 figure

    Neutral-Current Atmospheric Neutrino Flux Measurement Using Neutrino-Proton Elastic Scattering in Super-Kamiokande

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    Recent results show that atmospheric ΜΌ\nu_\mu oscillate with ÎŽm2≃3×10−3\delta m^2 \simeq 3 \times 10^{-3} eV2^2 and sin⁥22Ξatm≃1\sin^2{2\theta_{atm}} \simeq 1, and that conversion into Îœe\nu_e is strongly disfavored. The Super-Kamiokande (SK) collaboration, using a combination of three techniques, reports that their data favor ΜΌ→Μτ\nu_\mu \to \nu_\tau over ΜΌ→Μsterile\nu_\mu \to \nu_{sterile}. This distinction is extremely important for both four-neutrino models and cosmology. We propose that neutrino-proton elastic scattering (Îœ+p→Μ+p\nu + p \to \nu + p) in water \v{C}erenkov detectors can also distinguish between active and sterile oscillations. This was not previously recognized as a useful channel since only about 2% of struck protons are above the \v{C}erenkov threshold. Nevertheless, in the present SK data there should be about 40 identifiable events. We show that these events have unique particle identification characteristics, point in the direction of the incoming neutrinos, and correspond to a narrow range of neutrino energies (1-3 GeV, oscillating near the horizon). This channel will be particularly important in Hyper-Kamiokande, with ∌40\sim 40 times higher rate. Our results have other important applications. First, for a similarly small fraction of atmospheric neutrino quasielastic events, the proton is relativistic. This uniquely selects ΜΌ\nu_\mu (not ΜˉΌ\bar{\nu}_\mu) events, useful for understanding matter effects, and allows determination of the neutrino energy and direction, useful for the L/EL/E dependence of oscillations. Second, using accelerator neutrinos, both elastic and quasielastic events with relativistic protons can be seen in the K2K 1-kton near detector and MiniBooNE.Comment: 10 pages RevTeX, 8 figure

    APOSTEL 2.0 recommendations for reporting quantitative optical coherence tomography studies

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    OBJECTIVE: To update the consensus recommendations for reporting of quantitative optical coherence tomography (OCT) study results, thus revising the previously published Advised Protocol for OCT Study Terminology and Elements (APOSTEL) recommendations. METHODS: To identify studies reporting quantitative OCT results, we performed a PubMed search for the terms “quantitative” and “optical coherence tomography” from 2015 to 2017. Corresponding authors of the identified publications were invited to provide feedback on the initial APOSTEL recommendations via online surveys following the principle of a modified Delphi method. The results were evaluated and discussed by a panel of experts, and changes to the initial recommendations were proposed. A final survey was recirculated among the corresponding authors to obtain a majority vote on the proposed changes. RESULTS: One hundred sixteen authors participated in the surveys, resulting in 15 suggestions, of which 12 were finally accepted and incorporated into an updated 9-point-checklist. We harmonized the nomenclature of the outer retinal layers, added the exact area of measurement to the description of volume scans; we suggested reporting device-specific features. We advised to address potential bias in manual segmentation or manual correction of segmentation errors. References to specific reporting guidelines and room light conditions were removed. The participants’ consensus with the recommendations increased from 80% for the previous APOSTEL version to greater than 90%. CONCLUSIONS: The modified Delphi method resulted in an expert-led guideline (evidence class III, GRADE criteria) concerning study protocol, acquisition device, acquisition settings, scanning protocol, fundoscopic imaging, post-acquisition data selection, post-acquisition analysis, nomenclature and abbreviations, and statistical approach. It will still be essential to update these recommendations to new research and practices regularly

    Relationships with Alcohol: Utilizing Storytelling with Resistant Youth

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