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eta-meson photoproduction off protons and deuterons

C. Deutsch-Sauermann·B. Friman·W. Noerenberg
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Abstract

We present a unitary and gauge-invariant model with coupled channels, which provides a consistent description of pion photoproduction off nucleons in the E$_{0+}$ channel and eta-meson photoproduction off protons and deuterons. An effective field theory with hadrons and photons is constructed, which includes non-resonant Born terms as well as the S$_{11}$(1535) and S$_{11}$(1650) baryon resonances. Due to the coupling between the channels, the production of eta-mesons is strongly affected by the S$_{11}$(1650) although its direct coupling to the $η$N channel is negligible. The rho- and omega-meson exchange terms are important for achieving a consistent description of both pion- and photon-induced reactions.

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C. Deutsch-Sauermann, B. Friman, W. Noerenberg. 1997-01-14. eta-meson photoproduction off protons and deuterons. https://doi.org/10.1016/s0370-2693(97)00886-1

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