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Eta-N Final State Interaction in incoherent Photoproduction of Eta-mesons from the Deuteron near Threshold

A. Sibirtsev·S. Schneider·Ch. Elster·J. Haidenbauer·S. Krewald·J. Speth
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Abstract

An analysis of incoherent photoproduction of $η$ mesons off the deuteron for photon energies from threshold to 800 MeV is presented. The dominant contribution, the $γ$N-$η$N amplitude, is described within an isobar model. Effects of the final state interactions in the $NN$ as well as the $ηN$ systems are included employing models derived within the meson-exchange approach. It is found that their consideration is important. Specifically, due to an interference effect the influence of the $ηN$ final state interaction is enhanced in the reaction $γd \to np η$ close to threshold.

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A. Sibirtsev, S. Schneider, Ch. Elster, J. Haidenbauer, S. Krewald, J. Speth. 2001-11-30. Eta-N Final State Interaction in incoherent Photoproduction of Eta-mesons from the Deuteron near Threshold. https://doi.org/10.1103/physrevc.65.044007

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