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arXiv · 0705.3385

Model-independent extraction of two-photon effects in elastic electron-proton scattering

M. A. Belushkin·H. -W. Hammer·U. -G. Meißner
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Abstract

We address the discrepancy between the Rosenbluth and polarization transfer data for the electromagnetic form factors of the nucleon. Assuming that the effect of two-photon corrections on the polarization transfer data is negligible, we obtain a model-independent estimate of the two-photon correction Delta^(2γ). We analyze the polarization transfer data and the cross section data separately using dispersion relations. A central value as well as an error estimate for Delta^(2γ) is then obtained from a comparison of the two analyses. The resulting values for Delta^(2γ) are in good agreement with direct calculations available in the literature.

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M. A. Belushkin, H. -W. Hammer, U. -G. Meißner. 2007-05-23. Model-independent extraction of two-photon effects in elastic electron-proton scattering. https://doi.org/10.1016/j.physletb.2007.10.031

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