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Calculation of two-photon exchange effects for $Δ$ production in electron-proton collisions

S. Kondratyuk·P. G. Blunden
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Abstract

We present an evaluation of a two-photon exchange correction to the cross section for unpolarized $Δ$ isobar production in electron-proton collisions, using a relativistic, crossing symmetric and gauge invariant approach. The calculated box and crossed-box diagrams include nucleon and $Δ$ intermediate states. We find a relation between the angular nonlinearity of the two-photon exchange contribution and the value of the $γΔΔ$ coupling constant.

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S. Kondratyuk, P. G. Blunden. 2006-07-31. Calculation of two-photon exchange effects for $Δ$ production in electron-proton collisions. https://doi.org/10.1016/j.nuclphysa.2006.07.038

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