2,279,989 research outputs found

    Strange particle production in a single-freeze-out model

    Full text link
    The transverse-momentum spectra and elliptic flow of strange particles are calculated in the framework of the single-freeze-out model and compared with the recent RHIC data. An overall very good agreement between the model predictions and the data is obtained.Comment: talk presented by WF during the VIIIth Int. Conf. on Strangeness in Quark Matter, Cape Town, Sept. 15-20, 200

    Trions in a periodic potential

    Full text link
    The group-theoretical classification of trion states is presented. It is based on considerations of products of irreducible representations of the 2D translation group. For a given BvK period N degeneracy of obtained states is N^2. Trions consist of two identical particles so the symmetrization of states with respect to particles transposition is considered. Completely antisymmetric states can be constructed by introducing antisymmetric spin functions. Two symmetry adapted bases are considered. The third possibility is postponed for the further investigations.Comment: revtex, 5 p., sub. to Physica

    Connecting structure functions on the lattice with phenomenology

    Full text link
    We examine the extraction of moments of parton distributions from lattice data, focusing in particular on the chiral extrapolation as a function of the quark mass. Inclusion of the correct chiral behavior of the spin-averaged isovector distribution resolves a long-standing discrepancy between the lattice moments and experiment. We extract the x-dependence of the valence u-d distribution from the lowest few lattice moments, and discuss the implications for the quark mass dependence of meson masses lying on the rho Regge trajectory. The role of chiral symmetry in spin-dependent distributions, and in particular the lattice axial vector charge, g_A, is also highlighted.Comment: 8 pages, 5 figures, plenary talk given by W. Melnitchouk at the 3rd Circum-Pan-Pacific Symposium on High Energy Spin Physics (Beijing, China, October 2001), to appear in Int. J. Mod. Phys.

    Parton distributions from lattice QCD

    Get PDF
    We extract the x dependence of the nonsinglet u-d distribution function in the nucleon from the lowest few moments calculated on the lattice, using an extrapolation formula which ensures the correct behavior in the chiral and heavy quark limits. We discuss the implications for the quark mass dependence of meson masses lying on the J(PC)=1(--) Regge trajectory.Comment: 18 pages, 6 figures, minor changes made for publicatio

    Deep inelastic scattering from light nuclei

    Full text link
    We review recent developments in the study of deep inelastic scattering from light nuclei, focusing in particular on deuterium, helium, and lithium. Understanding the nuclear effects in these systems is essential for the extraction of information on the neutron structure function.Comment: 11 pages, 5 figures; talk given by W. Melnitchouk at the Workshop on Testing QCD through Spin Observables in Nuclear Targets, University of Virginia, April 200

    1973 Evaluations of Some Pesticide Residues in Food: The Monographs. Food and Agriculture Organization of the United Nations, Rome, 1975. 491 p. Available from Unipub, Box 433, Murray Hill Station, New York, NY 10016. $15.00.

    Get PDF
    (excerpt) The evaluations of residues on foodstuffs contained in these monographs were prepared by a joint meeting of an FA0 expert committee and a WHO expert committee on pesticide residues that met in Geneva and produced its report Pesticide Residues in Food published as WHO Technical Report Series No. 545 and FA0 Agricultural Studies No. 92 in 1974. Th
    corecore