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.
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Hammer, H.W. Nucleon form factors in dispersion theory. Eur. Phys. J. A 28 (Suppl 1), 49–57 (2006). https://doi.org/10.1140/epja/i2006-09-006-5
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DOI: https://doi.org/10.1140/epja/i2006-09-006-5