7,142 research outputs found

    An Integrated and Collaborative Approach for NASA Earth Science Data

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    Earth science research requires coordination and collaboration across multiple disparate science domains. Data systems that support this research are often as disparate as the disciplines that they support. These distinctions can create barriers limiting access to measurements, which could otherwise enable cross-discipline Earth science. NASA's Earth Observing System Data and Information System (EOSDIS) is continuing to bridge the gap between discipline-centric data systems with a coherent and transparent system of systems that offers up to date and engaging science related content, creates an active and immersive science user experience, and encourages the use of EOSDIS earth data and services. The new Earthdata Coherent Web (ECW) project encourages cohesiveness by combining existing websites, data and services into a unified website with a common look and feel, common tools and common processes. It includes cross-linking and cross-referencing across the Earthdata site and NASA's Distributed Active Archive Centers (DAAC), and by leveraging existing EOSDIS Cyber-infrastructure and Web Service technologies to foster re-use and to reduce barriers to discovering Earth science data (http://earthdata.nasa.gov)

    Effects of mill type (hammer vs roller) and particle size uniformity on growth performance, nutrient digestibility, and stomach morphology in finishing pigs

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    Two experiments were conducted to determine the effects of mill type and particle size uniformity on finishing pigs. In Exp. 1, 120 pigs, with an average initial weight of 105 lb, were fed corn-soybean meal-based diets for 57 d. The corn was milled so that all diets had an average mean particle size of 800 11m (± 20), yet differed in particle size uniformity (Sgw). To obtain the most uniform treatment (1.9 Sgw), corn was milled through a roller mill. The intermediate treatment (2.3 Sgw) was obtained by milling corn through a hammermill. The least uniform treatment (2.7 Sgw) was obtained by blending coarsely and finely ground corn. Growth performance of pigs was not affected by Sgw of the diet. However, digestibilities of DM, N, and GE increased as Sgw was reduced. In Exp. 2, 128 pigs, widl an average initial weight of 150 lb, were fed diets with corn milled to 450 JLm (± 7) in a hammermill or a roller mill. The hammermilled corn had an Sgw of 1.8 and the rollermilled corn had an Sgw of 2.0. The diets were fed in meal or pelleted form. There were no interactions among mill type and diet form. Digestibilities of DM and N were greater for the hammermilled treatments, but no growth performance differences were due to mill type. Pelleting increased ADG 9% and improved efficiency of gain by 5 %. Pelleting also increased the severity of stomach lesions. In conclusion, at 800 and 450 p.m, mill type did not affect growth performance. However, nutrient digestibilities were improved by decreasing variability in particle size, a response that merits further investigation.; Swine Day, Manhattan, KS, November 19, 199

    Testing the Higgs Mechanism in the Lepton Sector with multi-TeV e+e- Collisions

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    Multi-TeV e+e- collisions provide with a large enough sample of Higgs bosons to enable measurements of its suppressed decays. Results of a detailed study of the determination of the muon Yukawa coupling at 3 TeV, based on full detector simulation and event reconstruction, are presented. The muon Yukawa coupling can be determined with a relative accuracy of 0.04 to 0.08 for Higgs bosons masses from 120 GeV to 150 GeV, with an integrated luminosity of 5 inverse-ab. The result is not affected by overlapping two-photon background.Comment: 6 pages, 2 figures, submitted to J Phys G.: Nucl. Phy

    Probing EWSB Naturalness in Unified SUSY Models with Dark Matter

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    We have studied Electroweak Symmetry Breaking (EWSB) fine-tuning in the context of two unified Supersymmetry scenarios: the Constrained Minimal Supersymmetric Model (CMSSM) and models with Non-Universal Higgs Masses (NUHM), in light of current and upcoming direct detection dark matter experiments. We consider both those models that satisfy a one-sided bound on the relic density of neutralinos, Ωχh2<0.12\Omega_{\chi} h^2 < 0.12, and also the subset that satisfy the two-sided bound in which the relic density is within the 2 sigma best fit of WMAP7 + BAO + H0 data. We find that current direct detection searches for dark matter probe the least fine-tuned regions of parameter-space, or equivalently those of lowest Higgs mass parameter μ\mu, and will tend to probe progressively more and more fine-tuned models, though the trend is more pronounced in the CMSSM than in the NUHM. Additionally, we examine several subsets of model points, categorized by common mass hierarchies; M_{\chi_0} \sim M_{\chi^\pm}, M_{\chi_0} \sim M_{\stau}, M_{\chi_0} \sim M_{\stop_1}, the light and heavy Higgs poles, and any additional models classified as "other"; the relevance of these mass hierarchies is their connection to the preferred neutralino annihilation channel that determines the relic abundance. For each of these subsets of models we investigated the degree of fine-tuning and discoverability in current and next generation direct detection experiments.Comment: 26 pages, 10 figures. v2: references added. v3: matches published versio

    Background Rejection in the DMTPC Dark Matter Search Using Charge Signals

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    The Dark Matter Time Projection Chamber (DMTPC) collaboration is developing low-pressure gas TPC detectors for measuring WIMP-nucleon interactions. Optical readout with CCD cameras allows for the detection for the daily modulation in the direction of the dark matter wind, while several charge readout channels allow for the measurement of additional recoil properties. In this article, we show that the addition of the charge readout analysis to the CCD allows us too obtain a statistics-limited 90% C.L. upper limit on the ee^- rejection factor of 5.6×1065.6\times10^{-6} for recoils with energies between 40 and 200 keVee_{\mathrm{ee}}. In addition, requiring coincidence between charge signals and light in the CCD reduces CCD-specific backgrounds by more than two orders of magnitude.Comment: 8 pages, 6 figures. For proceedings of DPF 2011 conferenc

    Is it possible to estimate the Higgs Mass from the CMB Power Spectrum?

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    General Relativity and Standard Model are considered as a theory of dynamical scale symmetry with definite initial data compatible with the accepted Higgs mechanism. In this theory the Early Universe behaves like a factory of electroweak bosons and Higgs scalars, and it gives a possibility to identify three peaks in the Cosmic Microwave Background power spectrum with the contributions of photonic decays and annihilation processes of primordial Higgs, W, and Z bosons in agreement with the QED coupling constant, Weinberg's angle, and Higgs' particle mass of about 118 GeV.Comment: version to appear in Yadernaya Fizik
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