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The γn → ηn quasi-free cross section reveals a resonant structure at W ∼ 1.675 GeV. This structure may be a manifestation of a baryon resonance. A priori its propreties, the possibly narrow width and the strong photocoupling to the neutron, look surprising. This structure may also signal the existence of a narrow state.Meson photoproduction off the neutron offers an attractive tool to study certain baryon resonances. A single-quark transition model 1 predicts only weak photoexcitation of the D 15 (1675) resonance from the proton target. Photocouplings to the neutron calculated in the framework of this approach, are not small. An isobar model for η photo-and electroproduction η-MAID 2 also suggests significant contribution of the D 15 (1675) to η photoproduction on the neutron.

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