Helicity dependent and independent generalized parton distributions of the nucleon in lattice QCDP. Hägler1, J.W. Negele2, D.B. Renner2, W. Schroers2, T. Lippert3 and K. Schilling (LHPC Collaboration)3
1 Department of Physics and Astronomy, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
2 Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
3 Department of Physics, University of Wuppertal, D-42097 Wuppertal, Germany
(Received 15 October 2004 / Published online 08 February 2005)
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, , , HT, ET, and , all depending on the three variables x, ξ and 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.
PACS: 12.38.Gc Lattice QCD calculations - 14.20.Dh Protons and neutrons
Based on talk given by Ph.H.
© Società Italiana di Fisica, Springer-Verlag 2005