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arXiv · 0909.4736

Compilation and analysis of charge asymmetry measurements from electron and positron scattering on nucleon and nuclei

E. Tomasi-Gustafsson·M. Osipenko·E. A. Kuraev·Yu. Bystritsky
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Abstract

World data on the lepton-charge asymmetry in the elastic and inelastic lepton scattering off the proton and nuclei are compiled and discussed. After reviewing the published results, we compare the elastic data to a model calculation of the two-photon exchange mechanism. We show that the existing data do not provide any evidence for the two-photon contribution. At significance level 0.05 the data allow to exclude the two-photon exchange as an explanation for the difference between Rosenbluth and polarization measurements of proton electromagnetic form factors.

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E. Tomasi-Gustafsson, M. Osipenko, E. A. Kuraev, Yu. Bystritsky. 2012-06-05. Compilation and analysis of charge asymmetry measurements from electron and positron scattering on nucleon and nuclei. https://arxiv.org/abs/0909.4736

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