2,664 research outputs found

    Recent STAR results in high-energy polarized proton-proton collisions at RHIC

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    The STAR experiment at the Relativistic Heavy-Ion Collider at Brookhaven National Laboratory is carrying out a spin physics program in high-energy polarized p⃗+p⃗\vec{p}+\vec{p} collisions at s=200−500 \sqrt{s}=200-500\,GeV to gain a deeper insight into the spin structure and dynamics of the proton. One of the main objectives of the spin physics program at RHIC is the extraction of the polarized gluon distribution function based on measurements of gluon initiated processes, such as hadron and jet production. The STAR detector is well suited for the reconstruction of various final states involving jets, Ï€0\pi^{0}, π±\pi^{\pm}, e±^{\pm} and γ\gamma, which allows to measure several different processes. Recent results will be shown on the measurement of jet production and hadron production at s=200 \sqrt{s}=200\,GeV. The RHIC spin physics program has recently completed the first data taking period in 2009 of polarized p⃗+p⃗\vec{p}+\vec{p} collisions at s=500 \sqrt{s}=500\,GeV. This opens a new era in the study of the spin-flavor structure of the proton based on the production of W−(+)W^{-(+)} bosons. Recent STAR results on the first measurement of WW boson production in polarized p⃗+p⃗\vec{p}+\vec{p} collisions will be shown.Comment: 10 pages, 9 figures, Talk presented at the 26th Winter Workshop on Nuclear Dynamics, Ocho Rios, Jamaica, January 2-9, 2010 to be published in Journal of Physics: Conference Series (JPCS) The author may be contacted via: [email protected]

    Recent results from the STAR spin program at RHIC

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    The STAR experiment uses polarized p+p collisions at RHIC to determine the contributions to the spin of the proton from gluon spin and from orbital angular momentum of the quarks and gluons. Selective STAR measurements of the longitudinal double spin asymmetry for inclusive jet and inclusive hadron production are presented here. In addition, we report measurements of the transverse spin asymmetry for di-jet production at mid-rapidity and the transverse single-spin asymmetry for forward pi0 productionComment: 4 pages, 5 figures, presented at GHP06 conferenc

    Application of AIS Technology to Forest Mapping

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    Concerns about environmental effects of large scale deforestation have prompted efforts to map forests over large areas using various remote sensing data and image processing techniques. Basic research on the spectral characteristics of forest vegetation are required to form a basis for development of new techniques, and for image interpretation. Examination of LANDSAT data and image processing algorithms over a portion of boreal forest have demonstrated the complexity of relations between the various expressions of forest canopies, environmental variability, and the relative capacities of different image processing algorithms to achieve high classification accuracies under these conditions. Airborne Imaging Spectrometer (AIS) data may in part provide the means to interpret the responses of standard data and techniques to the vegetation based on its relatively high spectral resolution

    Dissipation and fragmentation of low-Q^2 scattered partons in Au-Au collisions at RHIC

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    Two-particle correlations and event-wise fluctuations in transverse momentum p_t are reported for Au-Au collisions at sqrt{s_{NN}} = 62 and 200 GeV on pseudorapidity (eta) and azimuth (phi). Distributions of all pairs of particles (no leading trigger particle) reveal jet-like correlations, or peaks at pair-wise opening angles of order 1 radian or less. The width of this same-side correlation peak increases dramatically on pseudorapidity and decreases on azimuth for increasing collision centrality. Evolution of the same-side peak with centrality suggests dissipation of low-Q^2 partons via strong coupling to an expanding bulk medium. p_t correlations, which provide access to temperature and/or velocity distributions in the colliding system, are also presented.Comment: 4 pages, 2 figures, conference poster write-u

    Support for global science: Remote sensing's challenge

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    Remote sensing uses a wide variety of techniques and methods. Resulting data are analyzed by man and machine, using both analog and digital technology. The newest and most important initiatives in the U. S. civilian space program currently revolve around the space station complex, which includes the core station as well as co-orbiting and polar satellite platforms. This proposed suite of platforms and support systems offers a unique potential for facilitating long term, multidisciplinary scientific investigations on a truly global scale. Unlike previous generations of satellites, designed for relatively limited constituencies, the space station offers the potential to provide an integrated source of information which recognizes the scientific interest in investigating the dynamic coupling between the oceans, land surface, and atmosphere. Earth scientist already face problems that are truly global in extent. Problems such as the global carbon balance, regional deforestation, and desertification require new approaches, which combine multidisciplinary, multinational research teams, employing advanced technologies to produce a type, quantity, and quality of data not previously available. The challenge before the international scientific community is to continue to develop both the infrastructure and expertise to, on the one hand, develop the science and technology of remote sensing, while on the other hand, develop an integrated understanding of global life support systems, and work toward a quantiative science of the biosphere

    Pilot land data system

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    The Pilot Land Data System (PLDS) is a multi-institutional effort directed towards solving the data access and management needs of scientists studying the land surface. Some of the hardware and software, which are now available, are reviewed

    Measurement of the cross section and longitudinal double-spin asymmetry for dijet production in polarized pp collisions at √ s = 200 GeV

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    We report the first measurement of the longitudinal double-spin asymmetry ALL for midrapidity dijet production in polarized pp collisions at a center-of-mass energy of √s=200 GeV. The dijet cross section was measured and is shown to be consistent with next-to-leading order (NLO) perturbative QCD predictions. ALL results are presented for two distinct topologies, defined by the jet pseudorapidities, and are compared to predictions from several recent NLO global analyses. The measured asymmetries, the first such correlation measurements, support those analyses that find positive gluon polarization at the level of roughly 0.2 over the region of Bjorken-x\u3e0.05

    A plea to implement robustness into a breeding goal: poultry as an example

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    The combination of breeding for increased production and the intensification of housing conditions have resulted in increased occurrence of behavioral, physiological, and immunological disorders. These disorders affect health and welfare of production animals negatively. For future livestock systems, it is important to consider how to manage and breed production animals. In this paper, we will focus on selective breeding of laying hens. Selective breeding should not only be defined in terms of production, but should also include traits related to animal health and welfare. For this we like to introduce the concept of robustness. The concept of robustness includes individual traits of an animal that are relevant for health and welfare. Improving robustness by selective breeding will increase (or restore) the ability of animals to interact successfully with the environment and thereby to make them more able to adapt to an appropriate husbandry system. Application of robustness into a breeding goal will result in animals with improved health and welfare without affecting their integrity. Therefore, in order to be ethically acceptable, selective breeding in animal production should accept robustness as a breeding goa

    Remote Sensing Information Sciences Research Group: Santa Barbara Information Sciences Research Group, year 4

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    Information Sciences Research Group (ISRG) research continues to focus on improving the type, quantity, and quality of information which can be derived from remotely sensed data. Particular focus in on the needs of the remote sensing research and application science community which will be served by the Earth Observing System (EOS) and Space Station, including associated polar and co-orbiting platforms. The areas of georeferenced information systems, machine assisted information extraction from image data, artificial intelligence and both natural and cultural vegetation analysis and modeling research will be expanded

    The application of artificial intelligence techniques to large distributed networks

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    Data accessibility and transfer of information, including the land resources information system pilot, are structured as large computer information networks. These pilot efforts include the reduction of the difficulty to find and use data, reducing processing costs, and minimize incompatibility between data sources. Artificial Intelligence (AI) techniques were suggested to achieve these goals. The applicability of certain AI techniques are explored in the context of distributed problem solving systems and the pilot land data system (PLDS). The topics discussed include: PLDS and its data processing requirements, expert systems and PLDS, distributed problem solving systems, AI problem solving paradigms, query processing, and distributed data bases
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