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We propose a physically motivated parametrization for the unpolarized generalized parton distributions, H and E, valid at both zero and non-zero values of the skewness variable, \zeta. Our approach follows a previous detailed study of the \zeta=0 case where H and E were determined using constraints from simultaneous fits of the experimental data on both the nucleon elastic form factors and the deep inelastic structure functions in the non singlet sector. Additional constraints at \zeta \neq 0 are provided by lattice calculations of the higher moments of generalized parton distributions. We illustrate a method for extracting generalized parton distributions from lattice moments based on a reconstruction using sets of orthogonal polynomials. The inclusion in our fit of data on Deeply Virtual Compton Scattering is also discussed. Our method provides a step towards a model independent extraction of generalized distributions from the data. It also provides an alternative to double distributions based phenomenological models in that we are able to satisfy the polynomiality condition by construction, using a combination of experimental data and lattice, without resorting to any specific mathematical construct., Comment: 29 pages, 8 figures; added references, changed text in several places

We derive a sum rule for the total quark angular momentum of a spin-one hadronic system within a gauge invariant decomposition of the hadron's spin. We show that the total angular momentum can be measured through deeply virtual Compton scattering experiments using transversely polarized deuteron targets., 4 pages, 2 figures, changes in text, figures changed, references changed

In this work we derive a sum rule for the angular momentum of a spin 1 hadronic system., Comment: 5 pages, to appear in Proceedings of XVIII International Workshop on Deep-Inelastic Scattering and Related Subjects, April 19 -23, 2010, Convitto della Calza, Firenze, Italy

We propose a physically motivated parametrization for the unpolarized generalized parton distributions, H and E, valid at both zero and non-zero values of the skewness variable, \zeta. At \zeta=0, H and E are determined using constraints from simultaneous fits of experimental data on both the nucleon elastic form factors and the deep inelastic structure functions. Lattice calculations of the higher moments constrain the parametrization at \zeta > 0. Our method provides a step towards a model independent extraction of generalized distributions from the data that is alternative to the mathematical ansatz of double distributions., Proceedings of DIS 2007, p.771-774, ISBN 978-3-935702-23-2, ISSN 1435-8077