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arXiv · 1610.05957

Two-photon-exchange effects in the unpolarized $μp$ scattering within the hadronic model

Hai-Qing Zhou
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Abstract

In this work, the two-photon-exchange (TPE) effects in the unpolarized $μp$ scattering are discussed within the hadronic model where the intermediate states $N,Δ$ and $σ$ are considered. The contribution from the $N$ intermediate is close to the results given by Ref. \cite{Tomalak2014} at the small $Q$ and there is a sizeable difference when $Q>0.25$GeV (where $Q^2$ is the four momentum transfer). The contributions from the $Δ$ and the $σ$ intermediate states are much smaller than that from the $N$ intermediate at the small $Q$. In the kinematic region with $k_i\subseteq [0.01,0.3]$ GeV and $Q \leq0.4$GeV (where $k_i$ is the three momentum of initial muon at Lab frame), a naive expression for the TPE contributions is given, which can be used directly for other analysis.

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Hai-Qing Zhou. 2016-10-19. Two-photon-exchange effects in the unpolarized $μp$ scattering within the hadronic model. https://doi.org/10.1103/physrevc.95.025203

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