John W Negele

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We present the resolution of a long-standing discrepancy between the moments of parton distributions calculated from lattice QCD and their experimental values. We propose a simple extrapolation formula for the moments of the nonsinglet quark distribution u-d, as a function of quark mass, which embodies the general constraints imposed by the chiral symmetry(More)
Citation Walker-Loud, A. et al. " Light hadron spectroscopy using domain wall valence quarks on an asqtad sea. Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. The MIT Faculty has made this article openly available. Please share how this access(More)
  • D Dolgov, R Brower, S Capitani, P Dreher, J W Negele, A Pochinsky +6 others
  • 2002
Moments of the quark density, helicity, and transversity distributions are calculated in unquenched lattice QCD. Calculations of proton matrix elements of operators corresponding to these moments through the operator product expansion have been performed on 16 3 × 32 lattices for Wilson fermions at β = 5.6 using configurations from the SESAM collaboration(More)
  • R Brower, S Chandrasekharan, J W Negele, U.-J Wiese
  • 2008
Since present Monte Carlo algorithms for lattice QCD may become trapped in a fixed topological charge sector, it is important to understand the effect of calculating at fixed topology. In this work, we show that although the restriction to a fixed topological sector becomes irrelevant in the infinite volume limit, it gives rise to characteristic finite size(More)
  • R Brower, Boston U, N Christ, M Creutz, P Mackenzie, J Negele +5 others
  • 2007
The implications of lattice field theory for particle physics go far beyond the traditional studies of low energy QCD phenomenology which are currently the major focus of the field. New strongly coupled field theories may well be discovered at LHC scales; for these the lattice will be the major tool. Also supersymmetry is important to many high energy(More)
Several new developments in the calculation and interpretation of hadron density-density correlation functions are presented. The asymptotic behavior of correlation functions is determined from a tree diagram path integral. A method is developed to use this behavior to correct for leading image contributions on a finite periodic spatial lattice and to(More)
  • M.-C Chu, J M Grandy, S Huang, J W Negele, W K Kellogg
  • 1993
Cooling is used as a lter on a set of gluon elds sampling the Wilson action to selectively remove essentially all uctuations of the gluon eld except for the instantons. The close agreement between quenched lattice QCD results with cooled and uncooled conngurations for vacuum correlation functions of hadronic currents and for density-density correlation(More)
In contrast to ensembles of singular gauge instantons, which are well known to fail to produce confinement, it is shown that effective theories based on ensembles of merons or regular gauge instantons do produce confinement. Furthermore, when the scale is set by the string tension, the action density, topological susceptibility, and glueball masses are(More)
Moments of unpolarized, helicity, and transversity distributions, electromagnetic form factors, and generalized form factors of the nucleon are presented from a preliminary analysis of lattice results using pion masses down to 359 MeV. The twist two matrix elements are calculated using a mixed action of domain wall valence quarks and asqtad staggered sea(More)