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We develop techniques to calculate the four Delta electromagnetic form factors using lattice QCD, with particular emphasis on the sub-dominant electric quadrupole form factor that probes deformation of the Delta. Results are presented for pion masses down to approximately 350 MeV for three cases: quenched QCD, two flavors of dynamical Wilson quarks, and three flavors of quarks described by a mixed action combining domain wall valence quarks and dynamical staggered sea quarks. The magnetic moment of the Delta is chirally extrapolated to the physical point and the Delta charge density distributions are discussed.
The magnetic dipole, the electric quadrupole and the Coulomb quadrupole amplitudes for the transition $gamma Nto Delta$ are evaluated both in quenched lattice QCD at $beta=6.0$ and using two dynamical Wilson fermions simulated at $beta=5.6$. The dipo
The electromagnetic nucleon to Delta transition form factors are evaluated using two degenerate flavors of dynamical Wilson fermions and using dynamical sea staggered fermions with domain wall valence quarks. The two subdominant quadrupole form facto
The magnetic dipole, the electric quadrupole and the Coulomb quadrupole amplitudes for the transition gamma Nto Delta are calculated in quenched lattice QCD at beta=6.0 with Wilson fermions. Using a new method combining an optimal combination of inte
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 giv
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