336 research outputs found

    MONTE CARLO SIMULATIONS OF MUON PRODUCTION

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    Muon production requirements for a muon collider are presented. Production of muons from pion decay is studied. Lithium lenses and solenoids are considered for focussing pions from a target, and for matching the pions into a decay channel. Pion decay channels of alternating quadrupoles and long solenoids are compared. Monte Carlo simulations are presented for production of πμ\pi \rightarrow \mu by protons over a wide energy range, and criteria for choosing the best proton energy are discussed.Comment: Latex uses mu95.sty, 19 pages, 5 postscript figures. A postscript file can be seen at URL http://www.cap.bnl.gov/~cap/mumu/important.html Search for Publication

    Healthcare workers as parents: attitudes toward vaccinating their children against pandemic influenza A/H1N1

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    <p>Abstract</p> <p>Background</p> <p>Both the health care workers (HCWs) and children are target groups for pandemic influenza vaccination. The coverage of the target populations is an important determinant for impact of mass vaccination. The objective of this study is to determine the attitudes of HCWs as parents, toward vaccinating their children with pandemic influenza A/H1N1 vaccine.</p> <p>Methods</p> <p>A cross-sectional questionnaire survey was conducted with health care workers (HCWs) in a public hospital during December 2009 in Istanbul. All persons employed in the hospital with or without a health-care occupation are accepted as HCW. The HCWs who are parents of children 6 months to 18 years of age were included in the study. Pearson's chi-square test and logistic regression analysis was applied for the statistical analyses.</p> <p>Results</p> <p>A total of 389 HCWs who were parents of children aged 6 months-18 years participated study. Among all participants 27.0% (n = 105) reported that themselves had been vaccinated against pandemic influenza A/H1N1. Two third (66.1%) of the parents answered that they will not vaccinate their children, 21.1% already vaccinated and 12.9% were still undecided. Concern about side effect was most reported reason among who had been not vaccinated their children and among undecided parents. The second reason for refusing the pandemic vaccine was concerns efficacy of the vaccine. Media was the only source of information about pandemic influenza in nearly one third of HCWs. Agreement with vaccine safety, self receipt of pandemic influenza A/H1N1 vaccine, and trust in Ministry of Health were found to be associated with the positive attitude toward vaccinating their children against pandemic influenza A/H1N1.</p> <p>Conclusions</p> <p>Persuading parents to accept a new vaccine seems not be easy even if they are HCWs. In order to overcome the barriers among HCWs related to pandemic vaccines, determination of their misinformation, attitudes and behaviors regarding the pandemic influenza vaccination is necessary. Efforts for orienting the HCWs to use evidence based scientific sources, rather than the media for information should be considered by the authorities.</p

    Muon Colliders

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    Muon Colliders have unique technical and physics advantages and disadvantages when compared with both hadron and electron machines. They should thus be regarded as complementary. Parameters are given of 4 TeV and 0.5 TeV high luminosity \mumu colliders, and of a 0.5 TeV lower luminosity demonstration machine. We discuss the various systems in such muon colliders, starting from the proton accelerator needed to generate the muons and proceeding through muon cooling, acceleration and storage in a collider ring. Problems of detector background are also discussed.Comment: 28 pages, with 12 postscript figures. To be published Proceedings of the 9th Advanced ICFA Beam Dynamics Workshop, AIP Pres

    Observation of electron-antineutrino disappearance at Daya Bay

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    The Daya Bay Reactor Neutrino Experiment has measured a non-zero value for the neutrino mixing angle θ13\theta_{13} with a significance of 5.2 standard deviations. Antineutrinos from six 2.9 GWth_{\rm th} reactors were detected in six antineutrino detectors deployed in two near (flux-weighted baseline 470 m and 576 m) and one far (1648 m) underground experimental halls. With a 43,000 ton-GW_{\rm th}-day livetime exposure in 55 days, 10416 (80376) electron antineutrino candidates were detected at the far hall (near halls). The ratio of the observed to expected number of antineutrinos at the far hall is R=0.940±0.011(stat)±0.004(syst)R=0.940\pm 0.011({\rm stat}) \pm 0.004({\rm syst}). A rate-only analysis finds sin22θ13=0.092±0.016(stat)±0.005(syst)\sin^22\theta_{13}=0.092\pm 0.016({\rm stat})\pm0.005({\rm syst}) in a three-neutrino framework.Comment: 5 figures. Version to appear in Phys. Rev. Let

    A side-by-side comparison of Daya Bay antineutrino detectors

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    The Daya Bay Reactor Neutrino Experiment is designed to determine precisely the neutrino mixing angle θ13\theta_{13} with a sensitivity better than 0.01 in the parameter sin22θ13^22\theta_{13} at the 90% confidence level. To achieve this goal, the collaboration will build eight functionally identical antineutrino detectors. The first two detectors have been constructed, installed and commissioned in Experimental Hall 1, with steady data-taking beginning September 23, 2011. A comparison of the data collected over the subsequent three months indicates that the detectors are functionally identical, and that detector-related systematic uncertainties exceed requirements.Comment: 24 pages, 36 figure

    Measurement of Charged Pion Production Yields off the NuMI Target

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    The fixed-target MIPP experiment, Fermilab E907, was designed to measure the production of hadrons from the collisions of hadrons of momenta ranging from 5 to 120 GeV/c on a variety of nuclei. These data will generally improve the simulation of particle detectors and predictions of particle beam fluxes at accelerators. The spectrometer momentum resolution is between 3 and 4%, and particle identification is performed for particles ranging between 0.3 and 80 GeV/c using dE/dxdE/dx, time-of-flight and Cherenkov radiation measurements. MIPP collected 1.42×1061.42 \times10^6 events of 120 GeV Main Injector protons striking a target used in the NuMI facility at Fermilab. The data have been analyzed and we present here charged pion yields per proton-on-target determined in bins of longitudinal and transverse momentum between 0.5 and 80 GeV/c, with combined statistical and systematic relative uncertainties between 5 and 10%.Comment: 15 pages, 13 figure

    Antiproton Production in p+Ap+A Collisions at AGS Energies

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    Inclusive and semi-inclusive measurements are presented for antiproton (pˉ\bar{p}) production in proton-nucleus collisions at the AGS. The inclusive yields per event increase strongly with increasing beam energy and decrease slightly with increasing target mass. The pˉ\bar{p} yield in 17.5 GeV/c p+Au collisions decreases with grey track multiplicity, NgN_g, for Ng>0N_g>0, consistent with annihilation within the target nucleus. The relationship between NgN_g and the number of scatterings of the proton in the nucleus is used to estimate the pˉ\bar{p} annihilation cross section in the nuclear medium. The resulting cross section is at least a factor of five smaller than the free pˉp\bar{p}-p annihilation cross section when assuming a small or negligible formation time. Only with a long formation time can the data be described with the free pˉp\bar{p}-p annihilation cross section.Comment: 8 pages, 6 figure

    Status of Muon Collider Research and Development and Future Plans

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    The status of the research on muon colliders is discussed and plans are outlined for future theoretical and experimental studies. Besides continued work on the parameters of a 3-4 and 0.5 TeV center-of-mass (CoM) energy collider, many studies are now concentrating on a machine near 0.1 TeV (CoM) that could be a factory for the s-channel production of Higgs particles. We discuss the research on the various components in such muon colliders, starting from the proton accelerator needed to generate pions from a heavy-Z target and proceeding through the phase rotation and decay (πμνμ\pi \to \mu \nu_{\mu}) channel, muon cooling, acceleration, storage in a collider ring and the collider detector. We also present theoretical and experimental R & D plans for the next several years that should lead to a better understanding of the design and feasibility issues for all of the components. This report is an update of the progress on the R & D since the Feasibility Study of Muon Colliders presented at the Snowmass'96 Workshop [R. B. Palmer, A. Sessler and A. Tollestrup, Proceedings of the 1996 DPF/DPB Summer Study on High-Energy Physics (Stanford Linear Accelerator Center, Menlo Park, CA, 1997)].Comment: 95 pages, 75 figures. Submitted to Physical Review Special Topics, Accelerators and Beam
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