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Phenomenological analysis of two-photon exchange effects in proton form factor measurements

Dmitry Borisyuk·Alexander Kobushkin
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Abstract

We perform a model-independent phenomenological analysis of experimental data on proton form factors ratio. We find that only one of the two photon exchange amplitudes, which we call $δG_M$, is responsible for the discrepancy between Rosenbluth and polarization methods. The linearity of Rosenbluth plots implies that $δG_M$ is approximately linear function of $ε$. The slope of $δG_M$ is extracted from experimental data and is shown to be consistent with theoretical calculations.

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Dmitry Borisyuk, Alexander Kobushkin. 2007-08-03. Phenomenological analysis of two-photon exchange effects in proton form factor measurements. https://doi.org/10.1103/physrevc.76.022201

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