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arXiv · 1807.06163

Charge and spin asymmetries in elastic lepton-nucleon scattering

Abstract

Elastic lepton scattering off of a nucleon has proved to be an efficient tool to study the structure of the hadron. Modern cross section and asymmetry measurements at Jefferson Lab require effects beyond the leading order Born approximation to be taken into account. Availability of unpolarized beams of both electrons and positrons in respective experiments would enable to reduce systematic uncertainties due to higher-order charge-odd contributions. In addition, information on an unpolarized electron-to-positron cross section ratio could serve as a test for theoretical models that provide predictions for charge-dependent radiative corrections to elastic lepton-nucleon scattering. Availability of polarized beams of leptons would allow for even more comprehensive study of higher-order effects as some of them are dominant in polarized lepton-nucleon scattering asymmetries. We present a brief overview of effects due to the lepton's charge and target's polarization on elastic lepton-nucleon scattering measurements.

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Oleksandr Koshchii, Andrei Afanasev. 2018-07-17. Charge and spin asymmetries in elastic lepton-nucleon scattering. https://doi.org/10.1063/1.5040205

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