Abstract.We discuss a new approach to reducing excited state contributions from two-and three-point correlation functions in lattice simulations. For the purposes of this talk, we focus on the ∆(1232) resonance and discuss how this new method reduces excited state contamination from two-point functions and mention how this will be applied to three-point functions to extract hadronic form factors. 11.15.Ha,12.38.Gc,13.40.Gp,14.20.Gk The calculation of the electromagnetic form factors for mesons and baryons is crucial to understanding the structure of hadronic states in QCD. However, they are notoriously difficult to both measure experimentally as well as calculate theoretically due to the complications that arise from the strong interactions. In the case of the ∆(1232) resonance, the form factors themselves are not currently experimentally accessible, although two of the form factors in the static limit are known (the charge) or measured to some degree (the magnetic dipole moment). For the nucleon, experimental results do exist for the form factors as a function of the momentum transfer. This makes a calculation of the nucleon form factors both a check of methodology as well as of QCD, and allows us to be confident that lattice results for the ∆ form factors are reasonable. PACS:The electromagnetic form factors of the ∆ are encoded in the matrix elementwhere u α is a Rarita-Schwinger vector-spinor describing the external ∆, and J µ = ∑ qq γ µ q is the vector current. The Lorentz structure of Γ is given, for example, in [1], and has four form factors F * 1,2,3,4 (Q 2 ) that are functions of Q 2 = −(p ′ − p) 2 alone. These form factors give rise, in the limit Q 2 → 0, to the electric charge, magnetic dipole moment, electric quadrupole moment, and magnetic octupole moment of the ∆.Of these moments, the charge is of course known, and from the PDG [2], we havewhere we have added all of the errors (including theoretical) in quadrature just to get an idea for how well these are determined experimentally. Thus, it is essential even for this simple quantity to have a well-determined lattice result. Some unquenched results were obtained using the form factor approach in [3] and using a background field technique [4], but there are several difficulties that arise in these different methods. For this work, we will focus on the difficulties with the form factor approach. These are determined by calculating the 3-point correlator:where FT is the Fourier Transform of the correlator, and χ is some appropriate interpolating operator for the ∆. In the large time limit t f ≫ t ≫ t i :Here we have schematically written this so that Z contains various overlap factors of the form 0|χ|∆ as well as other kinematic factors that are known. The dots denote contributions from excited states that are generally ignored.

Abstract. Working at twist 2 accuracy and assuming the dominance of the Generalized Parton Distribution H we study the helicity-dependent and independent cross sections measured in Hall A, the beam spin asymmetries measured in Hall B at Jefferson Laboratory and beam charge, beam spin and target spin asymmetries measured by Hermes. We extract the real and imaginary parts of the Compton Form Factor H , the latter being obtained with a 20-50 % uncertainty. We pay extra attention to the estimation of systematic errors on the extraction of H . We discuss our results and compare to other extractions as well as to the popular VGG model.

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Abstract. We examine the nucleon's electromagnetic form factors in a Poincaré-covariant Faddeev framework. The threequark core contributions to the form factors are obtained by employing a quark-diquark approximation. We implement the selfconsistent solution for the quark-photon vertex from its inhomogeneous Bethe-Salpeter equation. We find that the resulting transverse parts which add to the Ball-Chiu vertex have no significant impact on nucleon magnetic moments. The currentquark mass evolution of the form factors agrees with results from lattice QCD.

We propose to enhance the kaon identification capabilities of the GlueX detector by constructing an FDIRC (Focusing Detection of Internally Reflected Cherenkov) detector utilizing the decommissioned BaBar DIRC components. The GlueX FDIRC would significantly enhance the GlueX physics program by allowing one to search for and study hybrid mesons decaying into kaon final states. Such systematic studies of kaon final states are essential for inferring the quark flavor content of hybrid and conventional mesons. The GlueX FDIRC would reuse one-third of the synthetic fused silica bars that were utilized in the BaBar DIRC. A new focussing photon camera, read out with large area photodetectors, would be developed. We propose operating the enhanced GlueX detector in Hall D for a total of 220 days at an average intensity of 5 × 10 7 γ/s, a program that was conditionally approved by PAC39.