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arXiv · 0911.3619

Two-photon exchange corrections to the pion form factor

P. G. Blunden·W. Melnitchouk·J. A. Tjon
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Abstract

We compute two-photon exchange corrections to the electromagnetic form factor of the pion, taking into account the finite size of the pion. Compared to the soft-photon approximation for the infrared divergent contribution which neglects hadron structure effects, the corrections are found to be < 1% for small Q^2 (Q^2 < 0.1 GeV^2), but increase to several percent for Q^2 > 1 GeV^2 at extreme backward angles.

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P. G. Blunden, W. Melnitchouk, J. A. Tjon. 2009-12-21. Two-photon exchange corrections to the pion form factor. https://doi.org/10.1103/physrevc.81.018202

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