The ratio of $e^{\pm }p$ scattering cross sections predicted from the global fit of elastic $ep$ data

Abstract

We present predictions for the value of the cross section ratio $\sigma (e^{+}p\to e^{+}p)/\sigma (e^{-}p\to e^{-}p)$, determined from our fit of the elastic $ep$ cross section and polarization data. In this fit we took into account the phenomenological two-photon exchange dispersive correction. The cross section ratios which are expected to be measured by the VEPP-3 experiment are computed. The kinematical region which will be covered by the E04-116 JLab experiment is also considered. It is shown that for both experiments the predicted cross section ratios deviate from unity within more than $3\sigma$.

7 pages, 4 figures

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Cited by in corpus (6)

• Review of two-photon exchange in electron scattering
• Search for effects beyond the Born approximation in polarization transfer observables in $\vec{e}p$ elastic scattering
• Feasibility studies of the time-like proton electromagnetic form factor measurements with PANDA at FAIR
• High $Q^2$ behavior of the electromagnetic form factors in the relativistic hypercentral CQM
• Form factor ratio from unpolarized elastic electron proton scattering
• Two-photon exchange: myth and history