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

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.

11 pages (LaTeX), 7 postscript figures