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Helicity Dependent and Independent Generalized Parton Distributions of the Nucleon in Lattice QCD

Ph. Hagler·J. W. Negele·D. B. Renner·W. Schroers·T. Lippert·K. Schilling
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Abstract

A complete description of the nucleon structure in terms of generalized parton distributions (GPDs) at twist 2 level requires the measurement/computation of the eight functions H, E, \tilde H, \tilde E, H_T, E_T, \tilde H_T and \tilde E_T, all depending on the three variables x, ξand t. In this talk, we present and discuss our first steps in the framework of lattice QCD towards this enormous task. Dynamical lattice QCD results for the lowest three Mellin moments of the helicity dependent and independent GPDs are shown in terms of their corresponding generalized form factors. Implications for the transverse coordinate space structure of the nucleon as well as the orbital angular momentum (OAM) contribution of quarks to the nucleon spin are discussed in some detail.

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Ph. Hagler, J. W. Negele, D. B. Renner, W. Schroers, T. Lippert, K. Schilling. 2004-10-14. Helicity Dependent and Independent Generalized Parton Distributions of the Nucleon in Lattice QCD. https://doi.org/10.1140/epjad%2Fs2005-05-005-y

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