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arXiv · hep-ph/0404206

Beam normal spin asymmetry in elastic lepton-nucleon scattering

M. Gorchtein·P. A. M. Guichon·M. Vanderhaeghen
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Abstract

We discuss the two-photon exchange contribution to observables which involve lepton helicity flip in elastic lepton-nucleon scattering. This contribution is accessed through the spin asymmetry for a lepton beam polarized normal to the scattering plane. We estimate this beam normal spin asymmetry at large momentum transfer using a parton model and we express the corresponding amplitude in terms of generalized parton distributions.

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M. Gorchtein, P. A. M. Guichon, M. Vanderhaeghen. 2004-04-23. Beam normal spin asymmetry in elastic lepton-nucleon scattering. https://doi.org/10.1016/j.nuclphysa.2004.06.008

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