Nucleon form factors in dispersion theory

MAMI 2005

Abstract.

Dispersion relations provide a powerful tool to analyse the electromagnetic form factors of the nucleon in both the space-like and the time-like regions with constraints from other experiments, unitarity, and perturbative QCD. We give a brief introduction into dispersion theory for nucleon form factors and present first results from our ongoing form factor analysis. We also calculate the two-pion continuum contribution to the isovector spectral functions drawing upon the new high statistics measurements of the pion form factor by the CMD-2, KLOE, and SND collaborations.

PACS.

11.55.Fv Dispersion relations 13.40.Gp Electromagnetic form factors 14.20.Dh Protons and neutrons 

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Copyright information

© Società Italiana di Fisica and Springer-Verlag 2006

Authors and Affiliations

  1. 1.Helmholtz-Institut für Strahlen- und Kernhysik (Theorie)Universität BonnBonnGermany

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