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Lattice QCD can provide a direct determination of meson electromagnetic form factors, making predictions for upcoming experiments at Jefferson Lab. The form factors are a reflection of the bound-state nature of the meson and so these calculations give information about how confinement by QCD affects meson internal structure. The region of high squared (space-like) momentum-transfer, $Q^2$, is of particular interest because perturbative QCD predictions take a simple form in that limit that depends on the meson decay constant. We previously showed incite{jonnaff} that, up to $Q^2$ of 6 $mathrm{GeV}^2$, the form factor for a `pseudo-pion made of strange quarks was significantly larger than the asymptotic perturbative QCD result and showed no sign of heading towards that value at higher $Q^2$. Here we give predictions for real mesons, the $K^+$ and $K^0$, in anticipation of JLAB results for the $K^+$ in the next few years. We also give results for a heavier meson, the $eta_c$, up to $Q^2$ of 25 $mathrm{GeV}^2$ for a comparison to perturbative QCD in a higher $Q^2$ regime.
We evaluate the strange nucleon electromagnetic form factors using an ensemble of gauge configurations generated with two degenerate maximally twisted mass clover-improved fermions with mass tuned to approximately reproduce the physical pion mass. In
We evaluate the isovector nucleon electromagnetic form factors in quenched and full QCD on the lattice using Wilson fermions. In the quenched theory we use a lattice of spatial size 3 fm at beta=6.0 enabling us to reach low momentum transfers and a l
The semileptonic process, B --> pi l u, is studied via full QCD Lattice simulations. We use unquenched gauge configurations generated by the MILC collaboration. These include the effect of vacuum polarization from three quark flavors: the $s$ quark
We study the chiral behavior of the electromagnetic (EM) form factors of pion and kaon in three-flavor lattice QCD. In order to make a direct comparison of the lattice data with chiral perturbation theory (ChPT), we employ the overlap quark action th
The electromagnetic form factors of the proton and the neutron are computed within lattice QCD using simulations with quarks masses fixed to their physical values. Both connected and disconnected contributions are computed. We analyze two new ensembl