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Two-photon exchange at low Q^2

Dmitry Borisyuk·Alexander Kobushkin
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Abstract

We study two-photon exchange for elastic electron-proton scattering at low Q^2. Compact approximate formulae for the amplitudes are obtained. Numerical calculations are done for Q^2 < 0.1 GeV^2 with several realistic form factor parameterizations, yielding similar results. They indicate that the corrections to magnetic form factor can visibly affect cross-section and proton radii. For low-Q^2 electron-neutron scattering two-photon exchange corrections are shown to be negligibly small.

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Dmitry Borisyuk, Alexander Kobushkin. 2006-12-26. Two-photon exchange at low Q^2. https://doi.org/10.1103/physrevc.75.038202

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