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تسجيل مستخدم جديدThe ratio of $e^{pm}p$ scattering cross sections predicted from the global fit of elastic $ep$ data
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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 $3sigma$.
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Lubomir Pentchev (Thomas Jefferson National Accelerator Facility
, n Newport News
, Virginia
2020
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