Nucleon Form Factors in the Space- and Timelike Regions
نویسنده
چکیده
Dispersion relations provide a powerful tool to describe the electromagnetic form factors of the nucleon both in the spacelike and timelike regions with constraints from unitarity and perturbative QCD. We give a brief introduction into dispersion theory for nucleon form factors and present results from a recent form factor analysis. Particular emphasis is given to the form factors in the timelike region. Furthermore, some recent results for the spacelike form factors at low momentum transfer from a ChPT calculation by Kubis and Meißner are discussed.
منابع مشابه
Microscopic model of the timelike electromagnetic form factor of the nucleon.
A microscopic model of the electromagnetic form factor of the nucleon is developed in a hadronic framework, including pions, nucleons and the ∆-resonance explicitly. The space like on-shell form factors are reproduced and predictions for the half off-shell dependence are made. The impact of this off-shell dependence in the time like sector (q 2 < 1 GeV 2 , thus including the region of vector me...
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