Eur. Phys. J. A (2004) 19: 9-14
https://doi.org/10.1140/epjad/s2004-03-002-4

The structure of hadrons

Nucleon electromagnetic form factors from lattice QCD

Special Research Centre for the Subatomic Structure of Matter, and Department of Physics, University of Adelaide, Adelaide SA 5005 Australia

Received: 22 August 2004
Published online: 12 February 2004

Abstract

It is imperative that lattice QCD serve to develop our understanding of hadron structure and, where possible, to guide the interpretation of experimental data. There is now a great deal of effort directed at the calculation of the electroweak form factors of the nucleon, where for example, measurements at Jefferson Laboratory have recently revealed surprising behaviour in the ratio G _E /G _M . While, for the present, calculations within the framework of lattice QCD are limited to relatively large quark mass, there has been considerable progress in our understanding of how to extrapolate to the chiral limit. Here we report the results of the application of these techniques to the most recent form factor data from the QCDSF Collaboration. The level of agreement with all of the form factors, for Q ² below 1 GeV², is already impressive.