147 research outputs found

    Calorimetry for low-energy electrons using charge and light in liquid argon

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    Precise calorimetric reconstruction of 5–50 MeV electrons in liquid argon time projection chambers (LArTPCs) will enable the study of astrophysical neutrinos in DUNE and could enhance the physics reach of oscillation analyses. Liquid argon scintillation light has the potential to improve energy reconstruction for low-energy electrons over charge-based measurements alone. Here we demonstrate light-augmented calorimetry for low-energy electrons in a single-phase LArTPC using a sample of Michel electrons from decays of stopping cosmic muons in the LArIAT experiment at Fermilab. Michel electron energy spectra are reconstructed using both a traditional charge-based approach as well as a more holistic approach that incorporates both charge and light. A maximum-likelihood fitter, using LArIAT’s well-tuned simulation, is developed for combining these quantities to achieve optimal energy resolution. A sample of isolated electrons is simulated to better determine the energy resolution expected for astrophysical electron-neutrino charged-current interaction final states. In LArIAT, which has very low wire noise and an average light yield of 18  pe/MeV, an energy resolution of σ/E≃9.3%/√E⊕1.3% is achieved. Samples are then generated with varying wire noise levels and light yields to gauge the impact of light-augmented calorimetry in larger LArTPCs. At a charge-readout signal-to-noise of S/N≃30, for example, the energy resolution for electrons below 40 MeV is improved by ≈10%, ≈20%, and ≈40% over charge-only calorimetry for average light yields of 10  pe/MeV, 20  pe/MeV, and 100  pe/MeV, respectively.https://arxiv.org/abs/1909.07920Othe

    Multiple muon measurements with MACRO

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    The MACRO experiment at Gran Sasso provides means for detailed studies of multiple coincident penetrating cosmic ray muons. In this paper we concentrate on the studies of the ultrahigh energy primary cosmic ray composition using muon bundle multiplicities, muon pair lateral and angular separation distributions.Othe

    History of Papillion, Nebraska

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    A territory is opened for settlement and the people pour in. Homesteads spring up in all directions and soon towns begin to dot the landscape. A nucleus of local government is formed and, as time passes, it broadens and strengthens. The territory gradually develops into a state and takes its place in the nation. The coming to statehood lures more settlers, as well as speculators, and the cycle repeats--more homesteads; more towns; still more government. In this humble manner began the great state of Nebraska and with it the beautiful little town of Papillion

    A Simple Method for Measuring Deep Convection

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    The glass-pipe technology used for RAFOS floats is applied to the monitoring of convection in deep mixed layers. The velocity of a vertical current is estimated from the relationship between the drag force exerted on a float by the vertical current and the buoyancy force induced by the float\u27s resultant displacement from hydrostatic equilibrium. Tests conducted in the winters of 1990 and 1991 in the 18°C waters of the northwestern Sargasso Sea reveal definite convective events. Vertical velocities of both upwelling and downwelling plumes are estimated to approach maxima nearing 0.05 m s−1, with durations of up to 2 h. One float that crossed the Gulf Stream and entered the Newfoundland Basin showed evidence of very active vertical currents in the near-surface waters with maximum velocities greater than 0.09 m s−1

    Management of Large Erupting Complex Odontoma in Maxilla

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    We present the unusual case of a large complex odontoma erupting in the maxilla. Odontomas are benign developmental tumours of odontogenic origin. They are characterized by slow growth and nonaggressive behaviour. Complex odontomas, which erupt, are rare. They are usually asymptomatic and are identified on routine radiograph but may present with erosion into the oral cavity with subsequent cellulitis and facial asymmetry. This present paper describes the presentation and management of an erupting complex odontoma, occupying the maxillary sinus with extension to the infraorbital rim. We also discuss various surgical approaches used to access this anatomic area

    A Conceptual Enterprise Framework for Managing Scientific Data Stewardship

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    Scientific data stewardship is an important part of long-term preservation and the use/reuse of digital research data. It is critical for ensuring trustworthiness of data, products, and services, which is important for decision-making. Recent U.S. federal government directives and scientific organization guidelines have levied specific requirements, increasing the need for a more formal approach to ensuring that stewardship activities support compliance verification and reporting. However, many science data centers lack an integrated, systematic, and holistic framework to support such efforts. The current business- and process-oriented stewardship frameworks are too costly and lengthy for most data centers to implement. They often do not explicitly address the federal stewardship requirements and/or the uniqueness of geospatial data. This work proposes a data-centric conceptual enterprise framework for managing stewardship activities, based on the philosophy behind the Plan-Do-Check-Act (PDCA) cycle, a proven industrial concept. This framework, which includes the application of maturity assessment models, allows for quantitative evaluation of how organizations manage their stewardship activities and supports informed decision-making for continual improvement towards full compliance with federal, agency, and user requirements

    Triplet lifetime in gaseous argon

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    MiniCLEAN is a single-phase liquid argon dark matter experiment. During the initial cooling phase, impurities within the cold gas (<<140 K) were monitored by measuring the scintillation light triplet lifetime, and ultimately a triplet lifetime of 3.480 ±\pm 0.001 (stat.) ±\pm 0.064 (sys.) μ\mus was obtained, indicating ultra-pure argon. This is the longest argon triplet time constant ever reported. The effect of quenching of separate components of the scintillation light is also investigated
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