Dispersion theoretical analysis of the nucleon form factors
1 Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
2 ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
3 Universität Bonn, Helmholtz Institut für Strahlen- und Kernphysik, Bethe Center for Theoretical Physics, D-53115 Bonn, Germany
4 Forschungszentrum Jülich, Institute für Kernphysik (IKP-3), Institute for Advanced Simulation (IAS-4) and Jülich Center for Hadron Physics, D-52145 Jülich, Germany
Published online: 26 January 2017
We review the achievements of the project C.2, that deals with a dispersion theoretical analysis of the nucleon form factors. We have analyzed the world data for the space-like and time-like form factors to extract nucleon radii and vector meson coupling constants. Our proton charge radius rPE ≃ 0.85 fm has gained prominence in the so-called proton radius puzzle, see Ref. . We also have analyzed the strong energy dependence of the e+e− → p̅p amplitude at the nucleon-antinucleon threshold, two-photon exchange effects and isospin violation in the isovector nucleon form factors.
© The Authors, published by EDP Sciences, 2017
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