Dru B. Renner

Chiral Extrapolation of Lattice Moments of Proton Quark Distributions

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 of QCD. The inclusion of the leading nonanalytic behavior leads to an excellent description of both the lattice data and the experimental values of the moments.

Moments of nucleon generalized parton distributions in lattice QCD

Calculation of the moments of generalized parton distributions in lattice QCD requires more powerful techniques than those previously used to calculate the moments of structure functions. Hence, we present a novel approach that exploits the full information content from a given lattice configuration by measuring an overdetermined set of lattice observables to provide maximal statistical constraints on the generalized form factors at a given virtuality t. In an exploratory investigation using unquenched QCD configurations at intermediate sea quark masses, we demonstrate that our new technique is superior to conventional methods and leads to reliable numerical signals for the

Charmed-meson decay constants in three-flavor lattice QCD

n=2

Light hadron spectroscopy using domain wall valence quarks on an Asqtad sea

flavor singlet generalized form factors up to

Moments of nucleon light cone quark distributions calculated in full lattice QCD

3{\mathrm{GeV}}^{2}.

Resonance Parameters of the Rho-Meson from Lattice QCD

The contribution from connected diagrams in the flavor singlet sector to the total quark angular momentum is measured to an accuracy of the order of 1%.

Two-Flavor QCD Correction to Lepton Magnetic Moments at Leading Order in the Electromagnetic Coupling

We present the first lattice QCD calculation with realistic sea quark content of the D+-meson decay constant f(D+). We use the MILC Collaborations publicly available ensembles of lattice gauge fields, which have a quark sea with two flavors (up and down) much lighter than a third (strange). We obtain f(D+)=201+/-3+/-17 MeV, where the errors are statistical and a combination of systematic errors. We also obtain f(Ds)=249+/-3+/-16 MeV for the Ds meson.

Nucleon Axial Charge in Full Lattice QCD

We present a calculation of the light-hadron spectrum in full QCD using three-flavor Asqtad sea quarks and domain wall valence quarks. Calculations of meson masses, meson and baryon masses are performed on a lattice of spatial size

Four-flavour leading-order hadronic contribution to the muon anomalous magnetic moment

L\simeq 2.5