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arXiv · 1010.4808

Two-photon exchange in elastic electron-pion scattering

Dmitry Borisyuk·Alexander Kobushkin
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Abstract

We calculate two-photon exchange amplitude for the elastic electron-pion scattering in the dispersion-relation inspired approach, including both elastic and inelastic contributions. The latter was modelled as a sum of \rho and b_1(1235) meson contributions. We find that at Q^2 < 2 GeV^2 the elastic contribution is dominant, similarly to electron-proton scattering case. At higher Q^2 the inelastic contribution is not negligible, but still smaller than the elastic one. We also explain observed rapid amplitude growth at backward angles.

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Dmitry Borisyuk, Alexander Kobushkin. 2010-10-22. Two-photon exchange in elastic electron-pion scattering. https://doi.org/10.1103/physrevc.83.025203

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