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Contribution of spin 1/2 and 3/2 resonances to two-photon exchange effects in elastic electron-proton scattering

S. Kondratyuk·P. G. Blunden
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Abstract

We calculate contributions of hadron resonances to two-photon exchange effects in electron-proton scattering. In addition to the nucleon and P33 resonance, the following heavier resonances are included as intermediate states in the two-photon exchange diagrams: D13, D33, P11, S11 and S31. We show that the corrections due to the heavier resonances are smaller that the dominant nucleon and P33 contributions. We also find that there is a partial cancellation between the contributions from the spin 1/2 and spin 3/2 resonances, which results in a further suppression of their aggregate two-photon exchange effect.

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S. Kondratyuk, P. G. Blunden. 2007-02-13. Contribution of spin 1/2 and 3/2 resonances to two-photon exchange effects in elastic electron-proton scattering. https://doi.org/10.1103/physrevc.75.038201

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