83,504 research outputs found

    The First Moments of Nucleon Generalized Parton Distributions

    Get PDF
    We extrapolate the first moments of the generalized parton distributions using heavy baryon chiral perturbation theory. The calculation is based on the one loop level with the finite range regularization. The description of the lattice data is satisfactory and the extrapolated moments at physical pion mass are consistent with the results obtained with dimensional regularization, although the extrapolation in the momentum transfer to t=0t=0 does show sensitivity to form factor effects which lie outside the realm of chiral perturbation theory. We discuss the significance of the results in the light of modern experiments as well as QCD inspired models.Comment: 14 pages, 9 figure

    Young Member Programs for Cooperatives

    Get PDF
    The overall objective of this study is to provide cooperative decision makers with effective strategies for developing young member programs in local cooperatives. To accomplish this, the study sets out to determine: (1) the range and scope of young member programs and activities utilized by a sample of local cooperatives, (2) the relationship of young member programs and activities to the legislative system of local cooperatives, (3) the factors that block integration of young member programs and activities into local cooperatives and (4) the organizing procedures that help stimulate the development of young member programs and activities.Cooperative, young member, education, program, participation, Agribusiness,

    Phase transition from hadronic matter to quark matter

    Get PDF
    We study the phase transition from nuclear matter to quark matter within the SU(3) quark mean field model and NJL model. The SU(3) quark mean field model is used to give the equation of state for nuclear matter, while the equation of state for color superconducting quark matter is calculated within the NJL model. It is found that at low temperature, the phase transition from nuclear to color superconducting quark matter will take place when the density is of order 2.5ρ0\rho_0 - 5ρ0\rho_0. At zero density, the quark phase will appear when the temperature is larger than about 148 MeV. The phase transition from nuclear matter to quark matter is always first order, whereas the transition between color superconducting quark matter and normal quark matter is second order.Comment: 18 pages, 11 figure

    Interplay of Spin and Orbital Angular Momentum in the Proton

    Get PDF
    We derive the consequences of the Myhrer-Thomas explanation of the proton spin problem for the distribution of orbital angular momentum on the valence and sea quarks. After QCD evolution these results are found to be in very good agreement with both recent lattice QCD calculations and the experimental constraints from Hermes and JLab

    Quark structure and nuclear effective forces

    Get PDF
    We formulate the quark meson coupling model as a many-body effective Hamiltonian. This leads naturally to the appearance of many-body forces. We investigate the zero range limit of the model and compare its Hartree-Fock Hamiltonian to that corresponding to the Skyrme effective force. By fixing the three parameters of the model to reproduce the binding and symmetry energy of nuclear matter, we find that it allows a very satisfactory interpretation of the Skyrme force.Comment: 4 pages, 1tabl

    Statistical analysis of network data and evolution on GPUs: High-performance statistical computing

    Get PDF
    Network analysis typically involves as set of repetitive tasks that are particularly amenable to poor-man's parallelization. This is therefore an ideal application are for GPU architectures, which help to alleviate the tedium inherent to statistically sound analysis of network data. Here we will illustrate the use of GPUs in a range of applications, which include percolation processes on networks, the evolution of protein-protein interaction networks, and the fusion of different types of biomedical and disease data in the context of molecular interaction networks. We will pay particular attention to the numerical performance of different routines that are frequently invoked in network analysis problems. We conclude with a review over recent developments in the generation of random numbers that address the specific requirements posed by GPUs and high-performance computing needs

    Cyclic Quantum Error-Correcting Codes and Quantum Shift Registers

    Get PDF
    We transfer the concept of linear feed-back shift registers to quantum circuits. It is shown how to use these quantum linear shift registers for encoding and decoding cyclic quantum error-correcting codes.Comment: 18 pages, 15 figures, submitted to Proc. R. Soc.

    Liquid-gas phase transition in nuclear matter including strangeness

    Get PDF
    We apply the chiral SU(3) quark mean field model to study the properties of strange hadronic matter at finite temperature. The liquid-gas phase transition is studied as a function of the strangeness fraction. The pressure of the system cannot remain constant during the phase transition, since there are two independent conserved charges (baryon and strangeness number). In a range of temperatures around 15 MeV (precise values depending on the model used) the equation of state exhibits multiple bifurcates. The difference in the strangeness fraction fsf_s between the liquid and gas phases is small when they coexist. The critical temperature of strange matter turns out to be a non-trivial function of the strangeness fraction.Comment: 15 pages, 7 figure
    corecore