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arXiv · 0709.3370

Nucleon form factors on the lattice with light dynamical fermions

UKQCDSF Collaboration·Meinulf Gockeler·Philipp Hagler·Roger Horsley·Yoshifumi Nakamura·Munehisa Ohtani·Dirk Pleiter·Paul E. L. Rakow·Andreas Schafer·Gerrit Schierholz·Wolfram Schroers·Hinnerk Stuben·James M. Zanotti
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Abstract

The electromagnetic form factors provide important insight into the internal structure of the nucleon and continue to be of major interest for experiment and phenomenology. For an intermediate range of momenta the form factors can be calculated on the lattice. However, the reliability of the results is limited by systematic errors mostly due to the required extrapolation to physical quark masses. Chiral effective field theories predict a rather strong quark mass dependence in a range which was yet inaccessible for lattice simulations. We give an update on recent results from the QCDSF collaboration using gauge configurations with dynamical Nf=2, non-perturbatively O(a)-improved Wilson fermions at pion masses as low as 350 MeV.

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UKQCDSF Collaboration, Meinulf Gockeler, Philipp Hagler, Roger Horsley, Yoshifumi Nakamura, Munehisa Ohtani, Dirk Pleiter, Paul E. L. Rakow, Andreas Schafer, Gerrit Schierholz, Wolfram Schroers, Hinnerk Stuben, James M. Zanotti. 2009-03-24. Nucleon form factors on the lattice with light dynamical fermions. https://arxiv.org/abs/0709.3370

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