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Evidence for a narrow structure at W~1.68 GeV in eta photoproduction on the neutron

V. Kuznetsov·S. Churikova·G. Gervino·F. Ghio·B. Girolami·D. Ivanov·J. Jang·A. Kim·W. Kim·A. Ni·Yu. Vorobiev·M. Yurov·A. Zabrodin
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Abstract

New results on quasi-free $η$ photoproduction on the neutron and proton bound in a deuteron target are presented. The $γn \to ηn$ quasi-free cross section reveals a bump-like structure which is not seen in the cross section on the proton. This structure may signal the existence of a relatively narrow ($M\sim 1.68$ GeV, $Γ\leq 30$ MeV) baryon state.

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V. Kuznetsov, S. Churikova, G. Gervino, F. Ghio, B. Girolami, D. Ivanov, J. Jang, A. Kim, W. Kim, A. Ni, Yu. Vorobiev, M. Yurov, A. Zabrodin. 2007-03-21. Evidence for a narrow structure at W~1.68 GeV in eta photoproduction on the neutron. https://doi.org/10.1016/j.physletb.2007.01.041

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